9 prakash quizziz maths 2,8,13,14

If x - a is a factor of $x^3-3x^2a+2a^2x+b$ , then the value of b is 

• 0

• 2

• 1

• 3

If $x^{140}+2x^{151}+k$ is divisible by x + 1, then the value of k is 

• 1

• -3

• 2

• -2

One factor of  $x^4+x^2-20$ is  $x^2+5$ . The other factor is 

•  $x^2-4$  

•  $x-4$  

•  $x^2-5$  

•  $x+2$  

if  $x^2+\frac{1}{x^2}=\ 102,\$  then  $x\ -\ \frac{1}{x}=\ ?$  

• 8

• 10

• 12

• 13

If

 $\frac{a}{b}+\frac{b}{a}=\ -1,\ \ then\ \ \ \ \ a^3-\ b^3\ =\ ?$  

• 1

• -1

•  $\frac{1}{2}$  

• 0

Which of the following expressions is a polynomial in one variable?

• $x+\frac{2}{3}+3$

• $3\sqrt{x}+\frac{2}{\sqrt{x}}+5$

• $\sqrt{2}x^2-\sqrt{3}x+6$

• $x^{10}+y^5+8$

Which of the following is a binomial?

• $x^2+x+3$

• $x^2+4$

• $2x^2$

• $x+3+\frac{1}{x}$

Zero of the zero polynomial is

• 0

• 1

• every real number

• not defined

The class mark of the class 100-200 is

• 100

• 110

• 115

• 120

If the mean of five observations x ,x+2, x+4, x +6 and x+8 is 11, then the value of x is

• 5

• 6

• 7

• 8