If x + \(\frac{1}{x}\) = 21
then find the value of x2 + \(\frac{1}{x^2}\)
Answer & explanation
Correct answer: option 2
⇒ If x + \(\frac{1}{x}\) = a then x2 + \(\frac{1}{x^2}\) = a2 - 2
Here,
x + \(\frac{1}{x}\) = 21, then
⇒ x2 + \(\frac{1}{x^2}\) = 212 - 2 = 439