SOLUTION: Which of the following is equal to ( 1/a + a )^2 - ( 1/a – a )^2 ? a 0 b 4 c 1/a^2 - a^2 d 2/a^2 - 2a^2 e 1/a^2 - 4 - a^2

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: Which of the following is equal to ( 1/a + a )^2 - ( 1/a – a )^2 ? a 0 b 4 c 1/a^2 - a^2 d 2/a^2 - 2a^2 e 1/a^2 - 4 - a^2      Log On


   

Question 253003: Which of the following is equal to ( 1/a + a )^2 - ( 1/a – a )^2 ?
a 0 b 4 c 1/a^2 - a^2 d 2/a^2 - 2a^2 e 1/a^2 - 4 - a^2
Answer by palanisamy(496) About Me  (Show Source):
You can put this solution on YOUR website!
( 1/a + a )^2 = (1/a)2+a^2+2*(1/a)*a
(1/a + a )^2 = (1/a)2+a^2+2 ...(1)
Next,
( 1/a – a )^2 = (1/a)2+a^2-2*(1/a)*a
( 1/a – a )^2 = (1/a)2+a^2-2 ...(2)
(1)-(2) =>
( 1/a + a )^2 - ( 1/a – a )^2 = [(1/a)2+a^2+2]-[(1/a)2+a^2-2]
= (1/a)2+a^2+2-(1/a)2-a^2+2
= 4