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What are the coefficients in front of NO3-(aq) and Cu(s) when the following redox equation is balanced in an acidic solution:
___ NO3-(aq) + ___ Cu(s) → ___ NO(g) + ___ Cu2+(aq)?
A) 2, 6 B) 3, 6 C) 3, 4 D) 2, 3
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What is the frequency of a helium-neon laser light with a wavelength of 632.8 nm? The speed of light is #3.00 * 10^8 "m/s"#.
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The absorption of light of frequency 1.16 × 1011 Hz is required for CO molecules to go from the lowest rotational energy level to the next highest rotational energy level. Determine the energy for this transition in kJ/mol. h = 6.626 × 10-34 J · s ?
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What are the possible values of n and ml for an electron in a 5d orbital ?
A) n = 5 and ml = -2, -1, 0, +1, or +2
B) n = 1, 2, 3, 4, or 5 and ml = 2
C) n = 5 and ml = 2
D) n = 1, 2, 3, 4, or 5 and ml = -2, -1, 0, +1, or +2
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For hydrogen, what is the wavelength of the photon emitted when an electron drops from a 4d orbital to a 2p orbital in a hydrogen atom? The Rydberg constant is 1.097 × 10-2 nm-1.
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How many orbitals are there in the seventh shell ?
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The number of orbitals in a given subshell, such as the 5d subshell, is determined by the number of possible values of ?
A) l. B) n. C)ml. D) ms.
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First vibrational level for NaH lies at 1.154 × 10-20 J and the second vibrational level lies at 3.406 × 10-20 J. What is the frequency of the photon emitted when a molecule of NaH drops from the second vibrational level to the first vibrational level?
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Which of the following is not a valid set of quantum numbers?
A) n = 3, l = 0, ml = 0, and ms = 1/2 B) n = 2, l = 1, ml = -1, and ms = -1/2
C) n = 3, l = 2, ml = 3, and ms = 1/2 D) n = 2, l = 1, ml = 0, and ms = -1/2
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Of the following, which atom has the largest atomic radius?
A) Cl B) Br C) Na D) K
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What is the ground-state electron configuration of Co?
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How many unpaired electrons are in an atom of Co in its ground state ?
A) 7 B) 1 C) 3 D) 2
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What is the general valence-electron ground-state electron configuration for neutral alkaline earth metals?
A) ns2 B) 1s22s2 C) 1s22s1 D) ns1
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The phosphorus atom in PCl3 would be expected to have a ?
A) 3+ charge. B) partial negative (δ-) charge.
C) 3- charge. D) partial positive (δ+) charge.
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The Cl-Cl bond energy is 243 kJ/mol. Therefore the formation of a single bond between chlorine atoms ?
A) should require the absorption of 243 kJ per mole of #Cl_2# formed.
B) should result in the release of 243 kJ per mole of #Cl_2# formed.
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Of the following elements, which has the highest electronegativity ?
A) Sc B) P C) S D) As
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How many electrons are in the valence shell of I in IF4- ?
A) 14 B) 12 C) 10 D) 8
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How many lone pairs of electrons are on the P atom in PF3?
A) 2 B) 1 C) 0 D)3
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The molecule #SO_2# would be expected to have ? (A) two identical bonds intermediate between a single and a double bond (B) two single bonds (C) two double bonds (D) one single and one double bond
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Which one of the following is expected to exhibit resonance? (A) #CO_2# (B) #NH_4^(+)# (C) #HCN# (D) #NO_2""^(-)#
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The electronegativity is 2.1 for H and 1.8 for Si. Based on these electronegativities, #SiH_4# would be expected ?A) be ionic and contain H+ ions (B) be ionic and contain H- ions (C) have polar covalent bonds with a partial negative charges on the H atoms
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What is the molecular geometry of AsCl3 ?
A) tetrahedral B) trigonal pyramidal
C) trigonal planar D) T-shaped
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What geometric arrangement of charge clouds is expected for an atom that has five charge clouds ?
A) tetrahedral B) trigonal bipyramidal
C) octahedral D) square planar
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How many lone pairs of electrons are on the #Xe# atom in #XeF_6#?
A) 0 B) 3 C) 2 D) 1
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Which molecule contains a triple bond ?
A) HCN B) F2 C) O3 D) H2CO
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How many lone pairs are on the Br atom in BrF2- ?
A) 2 B) 3 C) 0 D) 1
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Which orbital hybridization is associated with a tetrahedral charge cloud arrangement ?
A) #sp# B) #sp^3d^2# C) #sp^3# D) #sp^2#
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What is the molecular geometry of BrF4- ?
A) square planar B) square pyramidal
C) seesaw D) tetrahedral
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What orbital hybridization is expected for the central atom in a molecule with a square planar geometry ?
A) sp3d B) sp3 C) sp2 D) sp3d2
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What is the smallest bond angle in #SF_6# ?
A) 109.5° B) 60° C) 120° D) 90°
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F(x)=(x^2-2x+4)/ (x-2),
f' (x)=(x^2-4x)/(x-2)^2 ,
f'' (x)=8/(x-2)^3
How to find the domain of f(x), x and y-intercepts, vertical asymptotes, the critical numbers, concave up and down and Sketch graph ?
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F(x)=2x^5/3 - 5x^4/3, f' (x)=10/3x^1/3(x^1/3 - 2) , f'' (x)=20(x^1/3 - 1) / 9x^2/3
How to find the domain of f(x), x and y-intercepts, vertical asymptotes, the critical numbers, concave up and down and Sketch graph ?
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A commodity has a demand function modeled by
p = 122 − 0.5x and a total cost function modeled by
C = 50x + 33.75, where x is the number of units.
(a) What price yields a maximum profit?
(b) When the profit is maximized, what is the average cost per unit
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How to find the derivative of x^2-y^2=1 by using the implicit differntiation ?
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How to find the derivative of xy=1 by using the implicit differentiation ?
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How to find the derivative of x^3+y^3=1 by using the implicit differentiation ?
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How to find the derivative of sqrt(x)+sqrt(y)=1 by using the implicit differentiation ?
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How to find the derivative of 16x^2 + 25y^2 =400 by using the implicit differentiation ?
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How to find the slope of the curve at the given point: x^2 + y^2 = 25 ; (3,-4) ?
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How to find the slope of the curve at the given point: xy = -8 ; (4,-2) ?
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Does the nature of intermolecular forces change when a substance
goes from a solid to a liquid, or from a liquid to a gas?
What causes a substance to undergo a phase change ?
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Why do liquids have a vapor pressure?Do all liquids have vapor pressures? Do solids exhibit vapor pressure? How does vapor pressure change with changing temperature?
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How does each of the following affect the rate of evaporation
of a liquid in an open dish?
a. intermolecular forces
b. temperature
c. surface area
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You have three covalent compounds with three very different
boiling points. All of the compounds have similar molar mass
and relative shape. Explain how these three compounds could
have very different boiling points ?
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How Identify the most important types of interparticle forces present
in the solids of each of the following substances ? a. #Ar# b. #CH_4# c. #HCl# d. #CO# e. #HF# f. #NaNO_3# g. #CaCl_2#
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How to predict which substance in each of the following pairs would
have the greater intermolecular forces ?
a) #CO_2# or #OCS#; b) #SeO_2# or #SO_2#; c) #CH_3CH_2CH_2NH_2# or #H_2NCH_2CH_2NH_2#; d) #CH_3CH_3# or #H_2CO#; e) #CH_3OH# or #H2CO#.
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How to show that of all the rectangles with a given perimeter, the
one with greatest area is a square ?
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How to find the area under the curve y=2x+4 from x=0 to x=2 ?
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How to find the area under the curve y= 3x^2+2 from x=0 to x=3 ?
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The following sum
√(7+(6/n)^2)*(6/n)+√(7+(612n)^2)*(6/n)+…+√(7+(6n/n)^2)*(6/n)
is a right Riemann sum with n subintervals of equal length for the definite integral
∫b and 5 f(x)dx
where b=
f(x)= ?
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Consider the function f(x)=((x^2/2)−3).
In this problem you will calculate [0,4]=[a,b]
((x2/2)−3)dx by using the definition.
Calculate Rn for f(x)=((x2/2)−3) on the interval [0,4] and write your answer as a function of n without any summation signs ?
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How do you evaluate the sum represented by ∑ with n^3 ?
Any examples
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Consider the integral given by [a,b]=[0,4].
(a) Find an approximation to this integral by using a Riemann sum with right endpoints and n = 8. Your answer should be correct to four decimal places.
R8= ?
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How do you evaluate the sum represented by #sum_(k=50)^300k^3#?
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How to evaluate the limit #lim_(n -> oo) sum_(j=1)^n(5j)/n^2#?
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What does it mean to write:
π av ± σ , or π av ± 2σ , or π av ± 3σ . How much % of normal data distribution is
included in each ?
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(a) Determine Δx and xi.
Δx=
xi=
(b) Using the definition mentioned above, evaluate the integral.
Value of integral: ?
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A car traveling 58.5 km/h is 27.4 m from a barrier when the driver slams on the brakes. The car hits the barrier 2.18 s later. (a) What is the car's constant deceleration magnitude before impact? (b) How fast is the car traveling at impact ?
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How to find all possible functions with the given derivative ?
If y′=sin(7t), then y =
If y′=cos(t/7), then y =
If y′=sin(7t)+cos(t/7), then y =
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How to find the function with derivative f′(x)=e^(7x) that passes through the point P=(0,8/7) ?
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When set the acceleration to the value required for the two balls to reach the finish line at the same time. Which of the following statements is/are true for this situation?
The balls has same acceleration
or same velocity or speed or al of above
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Consider a linear system whose augmented matrix is
first row (1 1 2 | 0)
second row (1 2 -3 | -1)
third row (9 19 k |-9)
For what value of k will the system have no solutions ?
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When considering the system
(−1x+2y= -13) and (2x−4y=26)
What are the solution to the system? If there are infinitely many solutions let y=t and solve for x in terms of t ?
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How to find (f) if f′(x)=16x^3+6x+7 and f(1)=−1 ?
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How to find a function f such that f′(x)=3x^3 and the line x+y=0 is tangent to the graph of f ?
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Given
f(x)=∫ (t^2−1)/(1+cos^2(t))dt
At what value of x does the local max of f(x) occur ?
(a=0 and b =x)
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G(x)=∫ tan(t)dt
How to find G(1)=
and
How to find G′(π/6)= ?
(a=1 & b=x)
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How to find the derivative of the following function
F(x)=∫ (2t−1)^3dt
(a=x^3 & b=x^4) ?
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An electric vehicle starts from rest and accelerates at a rate of 1.7 m/s^2 in a straight line until it reaches a speed of 22 m/s. The vehicle then slows at a constant rate of 1.5 m/s2 until it stops. (a) How much time elapses from start to stop?
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Compute your average velocity in the following two cases: (a) You walk 95.6 m at a speed of 1.92 m/s and then run 95.6 m at a speed of 3.19 m/s along a straight track. (b) You walk for 1.00 min at a speed of 1.92 m/s and then run for 1.50 min at 3.19 m/s?
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An electron with initial velocity v0 = 1.10 × 10^5 m/s enters a region 1.0 cm long where it is electrically accelerated (see the figure). It emerges with velocity v = 5.37 × 10^6 m/s. What is its acceleration, assumed constant?
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A car travels up a hill at a constant speed of 35 km/h and returns down the hill at a constant speed of 66 km/h. How to calculate the average speed for the round trip ?
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A muon (an elementary particle) enters a region with a speed of 4.85 × 10^6 m/s and then is slowed at the rate of 1.63 × 10^14 m/s^2. How far does the muon take to stop?
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Two trains, each having a speed of 24 km/h, are headed at each other on the same straight track. A bird that can fly 48 km/h flies off the front of one train when they are 48 km apart and heads directly for the other train ?
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A red car and a green car move toward each other in adjacent lanes and parallel to an x axis. At time t = 0, the red car is at xr = 0 and the green car is at xg = 216 m. If the red car has a constant velocity of 27.0 km/h ?
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At the instant the traffic light turns green, an automobile starts with a constant acceleration a of 2.1 m/s^2. At the same instant a truck, traveling with a constant speed of 9.2 m/s, overtakes and passes the automobile ?
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A pilot flies horizontally at 840 km/h, at height h = 48 m above initially level ground. However, at time t = 0, the pilot begins to fly over ground sloping upward at angle θ = 5.9° ?
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The graph gives the velocity v versus time t for a particle moving along an x axis. What is the particle's displacement from t = 0 to t = 16 s ?
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An electron has a constant acceleration of +2.4 m/s^2. At a certain instant its velocity is +9.3 m/s. What is its velocity (a) 1.6 s earlier and (b) 1.6 s later ?
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On a dry road, a car with good tires may be able to brake with a constant deceleration of 5.74 m/s^2. (a) How long does such a car, initially traveling at 29.3 m/s, take to stop? (b) How far does it travel in this time ?
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Two subway stops are separated by 1200 m. If a subway train accelerates at 1.4 m/s^2 from rest through the first half of the distance and decelerates at -1.4 m/s^2 through the second half, what are (a) its travel time and (b) its maximum speed ?
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A proton moves along the x axis according to the equation x = 88 t + 11 t^2, where x is in meters and t is in seconds ?
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A car moving with constant acceleration covered the distance between two points 52.4 m apart in 5.96 s. Its speed as it passes the second point was 14.6 m/s. (a) At what prior distance from the first point was the car at rest?
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How proof this answer is right ?
∫ ((1)/((x^2)(sqrt(1+x^2))dx =
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5(x1) +3(x2) +2(x3) =4 ,
3(x1) +3(x2)+2(x3) =2 ,
x2 + x3 = 5
How to find x1,x2,x3 ?
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How to determine whether the given matrix is invertible ?
first row (2,0)
second row(0,-5)
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The given matrix is invertible ?
first row ( -1 0 0 )
second row ( 0 2 0 )
third row ( 0 0 1/3 )
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How to find all the minors and cofactors of the matrix #A=((1, -2, 3), ( 6, 7, -1 ), (-3, 1, 4))#?
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If A and B are 3×2 matrices, and C is a 7×3 matrix, which of the following are defined?
A) C*A
B) C^T
C) B*C
D) A+B
E) B^T*C^T
F) C−A
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How to solve for X.
first row (8 ,-6) second row (-6,5) +4X= first row (-5,9) second row (4,4) ?
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A hot-air balloon is ascending at the rate of 12 m/s and is 51 m above the ground when a package is dropped over the side. (a) How long does the package take to reach the ground? (b) With what speed does it hit the ground ?
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A key falls from a bridge that is 50 m above the water. It falls directly into a model boat, moving with constant velocity, that is 18 m from the point of impact when the key is released. What is the speed of the boat ?
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A stone is dropped into a river from a bridge 46.5 m above the water. Another stone is thrown vertically down 1.28 s after the first is dropped. Both stones strike the water at the same time. What is the initial speed of the second stone ?
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A ball is shot vertically upward from the surface of another planet. A plot of y versus t for the ball is shown in the figure, where y is the height of the ball above its starting point and t = 0 at the instant the ball is shot ?
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A rock is shot vertically upward from the edge of the top of a tall building.The rock reaches its maximum height above the top of the building 1.60 s after being shot ?
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How far does the runner whose velocity–time graph is shown in the figure travel in 16 s? The figure's vertical scaling is set by vs = 9.00 m/s ?
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Let A be a 5 by 7 , B be a 7 by 6 and C be a 6 by 5 matrix. How to determine the size of the following matrices ?
AB, BA, A^TB, BC, ABC , CA ,B^TA , BC^T
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Is this matrix symmetric ?
first row ( 0,-7)
second row (-7,7)
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How to determine x and y such that ?
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How to determine whether a matrices are in echelon form, reduced echelon form or not in echelon form ?
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