MCQ
One factor of $x^4+x^2-20$ is $x^2+5$. The other factor is:
- ✓$x^2-4$
- B$x - 4$
- C$x^2-5$
- Dx + 4
✓
Answer
Correct option: A.
$x^2-4$
$x^4+x^2-20$
$=x^4+5 x^2-4 x^2-20$
$=x^2\left(x^2+5\right)-4(x^2+5)$
$=\left(x^2+5\right)\left(x^2-4\right)$
So, other factor is $\mathrm{x}^2-4$
$=x^4+5 x^2-4 x^2-20$
$=x^2\left(x^2+5\right)-4(x^2+5)$
$=\left(x^2+5\right)\left(x^2-4\right)$
So, other factor is $\mathrm{x}^2-4$
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Explore more
Similar questions
If a = 3 and b = 2 , then $(3 a-4 b)^{b-a} \div(4 a-3 b)^{2 b-a}$ is equal to
→$AB$ and $CD$ are two parallel lines. $PQ$ cuts $AB$ and $CD$ at $E$ and $F$ respectively. $EL$ is the bisector of $\angle\text{FEB}.$ If $\angle\text{LEB}=35^\circ,$ then $\angle\text{CFQ}$ will be:
→The number of triangles that can be drawn having angles as $50^\circ , 60^\circ $ and $70^\circ $ are:
→The cost of digging a pit of dimensions $4.5m × 2.5m × 2.5m$ at the rate of $₹ 20$ per cubic metre is:
→If $\bar{\text{x}}_1, \bar{\text{x}}_2, \bar{\text{x}}_3, ....., \bar{\text{x}}_\text{n}$ are the means of n group with $\mathrm{n}_1, \mathrm{n}_2, \ldots, \mathrm{n}_{\mathrm{n}}$ number of observations respectively, then the mean $\bar{\text{x}}$ of all the groups taken together is given by:
→In a $\triangle\text{ABC},$ if $\angle\text{A}=60^\circ,\angle\text{B}=80^\circ$ and the bisectors of $\angle\text{B}$ and $\angle\text{C}$ meet at $O$, then $\angle\text{BOC}=$
→In the given figure, side $BC$ of $\triangle\text{ABC}$ has been produced to a point $D$. If $\angle\text{A}=3\text{y}^\circ \angle\text{B}=\text{x}^\circ, \ \angle\text{C}=5\text{y}^\circ$ and $\angle\text{CBD}=7\text{y}^\circ.$ Then, the value of $x$ is: 
→Two equal circles of radius r intersect such that each passes through the centre of the other. The length of the common chord of the circle is:
If the area of an equilateral triangle is $16\sqrt{3}\text{cm}^2,$ then the perimeter of the triangle is:
→The equation y = - 4 in two variables x and y, can be written as