How do you write this easier ?

#(sqrt(3)-sqrt(2))/(sqrt(3)+sqrt(2)#

2 Answers
Aug 24, 2017

See a solution process below:

Explanation:

We can rationalize the denominator by multiplying this expression by the appropriate form of #1#

We can use this rule of quadratics to find the appropriate form of #1# to eliminate the radicals from the denominator:

#(color(red)(x) + color(blue)(y))(color(red)(x) - color(blue)(y)) = color(red)(x)^2 - color(blue)(y)^2#

And we can use this rule of quadratics to multiply the numerator:

#(color(red)(x) - color(blue)(y))(color(red)(x) - color(blue)(y)) = color(red)(x)^2 - 2color(red)(x)color(blue)(y) + color(blue)(y)^2#

#(color(red)(sqrt(3)) - color(blue)(sqrt(2)))/(color(red)(sqrt(3)) - color(blue)(sqrt(2))) xx (color(red)(sqrt(3)) - color(blue)(sqrt(2)))/(color(red)(sqrt(3)) + color(blue)(sqrt(2))) => #

#(color(red)(sqrt(3))^2 - 2color(red)(sqrt(3))color(blue)(sqrt(2)) + color(blue)(sqrt(2))^2)/(color(red)(sqrt(3))^2 - color(blue)(sqrt(2))^2) =>#

#(3 - 2sqrt(3 * 2) + 2)/(3 - 2) =>#

#(3 + 2 - 2sqrt(6))/1 =>#

#5 - 2sqrt(6)#

Aug 24, 2017

#5-2sqrt6#

Explanation:

#"what we have to do here is "color(blue)"rationalise the denominator"#

#"this means eliminating the radicals on the denominator"#
#"and replacing them with a rational value "#

#"this is achieved by multiplying the numerator and"#
#"denominator by the "color(blue)"conjugate ""of the denominator"#

#"the conjugate of "sqrt3+sqrt2" is "sqrt3color(red)(-)sqrt2#

#"note " sqrtaxxsqrta=a" and "sqrtaxxsqrtbhArrsqrt(ab)#

#rArr(sqrt3+sqrt2)(sqrt3-sqrt2)larr" expand using FOIL"#

#=3cancel(-2sqrt3)cancel(+2sqrt3)-2#

#=1larrcolor(red)" rational value"#

#rArr(sqrt3-sqrt2)/(sqrt3+sqrt2)#

#=((sqrt3-sqrt2)(sqrt3-sqrt2))/((sqrt3+sqrt2)(sqrt3-sqrt2))#

#=(3-sqrt6-sqrt6+2)/1#

#=5-2sqrt6#