MCQ
If $x^3 + 6x^2 + 4x +k$ is exactly divisible by $x + 2$ then $k =$
- A$-8$
- ✓$-7$
- C$-6$
- D$-10$
✓
Answer
Correct option: B.
$-7$
$-8$
$f(x) = x^3 + 6x^2 + 4x + k$
$f(-2) = 0$
$\therefore (-2)^3 + 6(-2)^2 + 4(-2) + k = 0$
$\therefore -8 + 6(4) + (-8) + k = 0$
$24 - 16 + k = 0$
$k + 8 = 0$
$k = -8$
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
The graph of y = 6 is a line
The length of each side of a rhombus is $10\ cm$ and one if its diagonals is of length $16\ cm.$ The length of the other diagonal is:
→In the given figure, $AB > AC$. Then which of the following is true?
→Write the correct answer in the following: Euclid divided his famous treatise “The Elements” into:
The figure formed by joining the mid-points of the adjacent sides of a quadrilateral is a:
If the measure of angles of a triangle are in the ratio of $3 : 4 : 5$, what is the measure of the smallest angle of the triangle?
→If every side of a triangle is doubled, then increase in the area of the triangle is:
Write the correct answer in the following: The value of $\frac{\sqrt{32}+\sqrt{48}}{\sqrt{8}+\sqrt{12}}$ is equal to
→The ratio of the volumes of a right circular cylinder and a right circular cone of the same base and the same height will be:
$(125)^{-\frac{1}{3}}=?$
→