Question #d2a0e

2 Answers
Nov 23, 2017

See below

Explanation:

#f(t) = 1/(sqrt(t+1))#
#f(y^2-1) = 1/(sqrt((y^2-1)+1))# (Replaced t by #y^2-1#

Simplifying further

#f(y^2-1) = 1/(pmy)#

#f(w-1)^2 = 1/(sqrt((w-1)^2+1))# (Replaced t by #(w-1)^2#

Simplifying further

#f(w-1)^2 = 1/(sqrt(w(w-2)+2)#

Nov 23, 2017

See explanation.

Explanation:

#color(blue)("Preamble")#

#f# is just a name given to a particular expression construction

The part in the brackets is what is used in that construction at designated points.

#f("something") =1/sqrt("something" + 1)#

Suppose we have #s# then

#f(s)=1/sqrt(s + 1)#

Suppose we have #b# then

#f(b)=1/sqrt(b + 1)#

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
#color(blue)("Answering the question")#

#f(color(green)(y^2-1))=1/sqrt(color(green)(y^2-1) + 1) = 1/sqrt(color(magenta)(y^2))=1/(+-y)#

Note that #color(magenta)(y^2)# will be a positive value but the square root of a positive value can be either positive or negative
.....................................................................................................

#f( color(red)([w-1]^2)) = 1/sqrt(color(red)([w-1]^2)+1) =1/sqrt(w^2-2w+2)#

Note that #(-1)^2=+1#