If x2 - 43x + 1= 0
and x > 1, then the value of
x2 + \(\frac{1}{x^2}\) will be:
Answer & explanation
Correct answer: option 3
If x2 - 43x + 1= 0
Divide by x on both sides,
x + \(\frac{1}{x}\) = 43
x2 + \(\frac{1}{x^2}\) = 432 - 2 = 1847
⇒ If x + \(\frac{1}{x}\) = a then x2 + \(\frac{1}{x^2}\) = a2 - 2