Practicing Success
If $(x+\frac{1}{x})^3=27$, then what is the value of $(x^2 + \frac{1}{x^2})$ ? Given that x is real. |
11 25 7 9 |
7 |
We know that, If $K+\frac{1}{K}=n$ then, $K^2+\frac{1}{K^2}$ = n2 – 2 If $(x+\frac{1}{x})^3=27$, then what is the value of $(x^2 + \frac{1}{x^2})$ = ? If $(x+\frac{1}{x})^3=27$ then, If $(x+\frac{1}{x})=\sqrt[3]{27}$ = 3 So, $(x^2 + \frac{1}{x^2})$ = 32 – 2 = 7 |