# 12th Mathematics - One Mark Questions - Part two

This set contains questions 9-16 provided to help students to practice them as a sample. After you have prepared well for your examinations, give these a questions a go to see how well you have prepared. Post your answers to this questions in the comments section..Refer here for questions 1-8.

9) The centre and radius of the sphere given by $2x^2+2y^2+2z^2-12x+16y-20z+2=0$ is :

a) (-3, 4, –5) : 49

b) (-6, 8, –10) : 7

c) (6, –8, 10) : 7

d) (3, –4, 5) : 7

10) The shortest distance of the point (2, 10, 1) from the plane $\overrightarrow{r}.(3\overrightarrow{i}-\overrightarrow{j}+4\overrightarrow{k})=2\sqrt{26}$ is:

a) $\sqrt{26}$

b) $2\sqrt{26}$

c) $2$

d) $\frac{1}{\sqrt26}$

11) The complex number 0, $0, z, z+\overrightarrow{z}, \overrightarrow{z}$ are the vertices of a :

a) square

b) parallelogram

c) rectangle

d) rhombus

12) if $\omega$ is a cube root of unit, then the value of $\frac{a+b\omega+c\omega^2}{a\omega+b\omega^2+c}+\frac{a\omega^2+b\omega+c}{a+b\omega^2+c\omega}$ is:

a) $2\omega$

b) $-2\omega^2$

c) $2\omega^2$

d) $-2\omega$

13) If z represents a complex number then $arg\; Z+arg \; \overrightarrow{Z}$ is:

a) $\frac{\pi}{4}$

b) $\frac{\pi}{3}$

c) $\frac{\pi}{2}$

d) 0

14) The polar form of the complex number $(i^{25})^3$ is:

a) $cos\pi-isin\pi$

b) $cos\frac{\pi}{2}-isin\frac{\pi}{2}$

c) $cos\pi+isin\pi$

d) $cos\frac{\pi}{2}+isin\frac{\pi}{2}$

15) The locus of the foot of the perpendicular from the focus on a tangent to the curve $16x^2+25y^2=400$ is:

a) $x^2+y^2=25$

b) $x^2+y^2=4$

c) $x^2+y^2=16$

d) $x^2+y^2=9$

16) One of the foci of the rectangular hyperbola xy = 18 is:

a) (6, 6)

b) (3, 3)

c) (4, 4)

d) (5, 5)