\inline\\\text{Als}\;\;x+\frac1x=y\;\;\text{dan is}\\\\ x^2+\frac{1}{x^2}\;\;\;\text{gelijk aan} A.   y − 2
B.   y + 2
C.   y2
D.   y2 − 2
E.   y2 + 2
    A    B    C    D    E

[ 3-1305 - op net sinds 29.7.2026-(E)- ]

Translation in   E N G L I S H

IN CONSTRUCTION

Oplossing - Solution

We kwadrateren de gelijkheid :
\inline\left(x+\frac1x \right)^2=y^2\\ \Rightarrow x^2+2.x.\frac1x+\frac{1}{x^2}=y^2\\ \Rightarrow x^2+2+\frac{1}{x^2}=y^2\\ \Rightarrow x^2+\frac{1}{x^2}=y^2-2

GWB