Find the zeroes of the following polynomial by the factorisation method and verify the relationship between the zeroes and the coefficients of the polynomial: $4x^{2} + 5\sqrt{2}x - 3$

Vedclass pdf generator app on play store
Vedclass iOS app on app store
(N/A) Let $f(x) = 4x^{2} + 5\sqrt{2}x - 3$.
To factorise,we split the middle term: $4x^{2} + 6\sqrt{2}x - \sqrt{2}x - 3$.
$= 2\sqrt{2}x(\sqrt{2}x + 3) - 1(\sqrt{2}x + 3)$.
$= (\sqrt{2}x + 3)(2\sqrt{2}x - 1)$.
Setting $f(x) = 0$,we get $\sqrt{2}x + 3 = 0$ or $2\sqrt{2}x - 1 = 0$.
Thus,the zeroes are $x = -\frac{3}{\sqrt{2}}$ and $x = \frac{1}{2\sqrt{2}}$.
Verification:
Sum of zeroes $= -\frac{3}{\sqrt{2}} + \frac{1}{2\sqrt{2}} = \frac{-6 + 1}{2\sqrt{2}} = -\frac{5}{2\sqrt{2}} = -\frac{5\sqrt{2}}{4}$.
Coefficient of $x$ is $5\sqrt{2}$ and coefficient of $x^{2}$ is $4$. So,$-\frac{\text{Coefficient of } x}{\text{Coefficient of } x^{2}} = -\frac{5\sqrt{2}}{4}$. (Verified)
Product of zeroes $= (-\frac{3}{\sqrt{2}}) \times (\frac{1}{2\sqrt{2}}) = -\frac{3}{4}$.
Constant term is $-3$ and coefficient of $x^{2}$ is $4$. So,$\frac{\text{Constant term}}{\text{Coefficient of } x^{2}} = -\frac{3}{4}$. (Verified)

Explore More

Similar Questions

Obtain the value of the following polynomial at the given value of $x$: $p(x) = x^{4} + 2x^{3} - x + 2$; at $x = 2$.

Find the number of real zeros of the following polynomial: $p(x) = x^{2} - 2x$.

Divide $x^{4}-3 x^{2}+4 x+5$ by $x^{2}-x+1$.

Difficult
View Solution

If $\alpha, \beta$ and $\gamma$ are the zeros of the cubic polynomial $p(x) = x^{3} + x^{2} - 17x + 15$,then $\alpha\beta + \beta\gamma + \gamma\alpha = \dots$

Are the following statements 'True' or 'False'? Justify your answers.
If all the zeroes of a cubic polynomial are negative,then all the coefficients and the constant term of the polynomial have the same sign.

Vedclass Products

For Students

Vedclass Test Series

Mock tests in real JEE/NEET style with performance analysis. 5-day free trial.

Start Free Trial
For Teachers

Exam Paper Generator

Generate Set A/B/C/D exam papers from 7.5L+ questions in 2 minutes. 3 chapters free.

Try Free
For Institutes

Online Exam Module

Live online exams with unlimited students, 360° analytics & white-label branding.

See Demo