Question

if a+1/a=4,then find a2-1/a2=?

Answer 1

A+1/a=4

squaring both sides we get

a2+1/a2+2*a*1/a=16

a and 1/a will cancel out each other so we are left with

a2+1/a2+2=16

a2+1/a2=14

Answer 2

hope it helps.............