GMAT Math Practice Test #1

Answer B: a²-b²=(a+b)X(a-b). So the given value is equal to 1²-(Ѵ3)²=-2

Key takeaway: The square root of the numbers like √3 is a decimal number and expression would require long calculation if we put in the given. So look for a way to attack such problems other way than straight arithmetic calculation. You should be able to find application of simple algebraic formulae.