Question

compute
(2^-3-2^-4) (2^-3+2^-4)​

Answer 1

= (2^-3-2^-4) (2^-3+2^-4)

by (a+b)(a-b) = a²-b²

= (1/8)²- (1/16)²

= 1/8×8 - 1/16×16

= 4/8×8×4 - 1/16×16

= 3/8×8×4

= 3/256

Answer 2

(2^-3-2^4)(2^-3+2^-4)
(2^-3)² - (2^4)²