Question

if a+1/a=-2 then a²+1/a²​

Answer 1

Answer:

a+1/a=-2

squaring both sides

(a+1/a)²=(-2)²

here formula (a+b)²= a²+2ab+b² will apply

(a)²+2(a)(1/a)+(1/a)²= (-2)²

a²+2+1/a²= 4. (a)(1/a) will be cancelled as both are multiplicative inverse

now

subtract 2 from both sides

a²+1/a²+2-2= 4-2

a²+1/a² = 2

here is the answer