Question #27, Arithmetic Session 7 Video Time Stamp 42:39

GRE Quant Problem Solving
1

hello! from arithmetic and algebra session 7, question 27 from time stamp 42:39, why isnt the answer 1? I distributed the exponent to get: (sqrt3)^2 - (sqrt2)^2 which helped cancel the square roots and then subtracted 3-2 to get the answer of 1.

Additionally, why cant i solve it as combining the roots and having (sqrt3-2)^2 therefore (sqrt1)^2, giving the answer of 1.

2

(a - b)^2 \neq a^2 - b^2

In fact, (a - b)^2 = a^2 - 2ab + b^2 so yeah you’re missing the -2ab term in your calculation.