Question

Lesson: Identities

Q: Solve using correct identity
x-1/x= 3 then x^2+1/x^2=? (tell the identity used)

PLEASE ANSWER FAST

Answer 1

Answer:

11

Step-by-step explanation:

$x-\frac{1}{x} =3\\\(x-\frac{1}{x})^{2} =3^{2} \\\x^{2} +\frac{1}{x^{2}} - 2(x)(\frac{1}{x} ) = 9\\x^{2} +\frac{1}{x^{2}} -2= 9\\x^{2} +\frac{1}{x^{2}}=9+2=11$

Identity used is $(a-b)^2=a^2+b^2-2ab$