First slide

Theory of equations

Question

If f(x) is a polynomial of degree 4 with rational coefficients and touches x-axis at $(\sqrt{2}, 0)$ , then for the equation f(x) = 0,

Moderate

A

sum of roots is $4 \sqrt{2}$
B

sum of roots is 0
C

product of roots is -4
D

product of roots is 4

Solution

It is given that f(x) touches x-axis at $(\sqrt{2}, 0)$ . So, two roots are $\sqrt{2}, \sqrt{2}$ .
Sine coefficients are rational, other roots must be $- \sqrt{2}, - \sqrt{2}$ .

Get Instant Solutions

When in doubt download our app. Now available Google Play Store- Doubts App

Recieve an sms with download link

Doubts App

OR

SCAN ME

Doubts App

Doubts App