English Medium इयत्ता ९ - CBSE Question Bank Solutions for Mathematics

In a quadrilateral ABCD, ∠A + ∠C is 2 times ∠B + ∠D. If ∠A = 140° and ∠D = 60°, then ∠B=

Name the smallest angle in each of these triangles:
In ΔXYZ, XY = 6.2cm, XY = 6.8cm and YZ = 5cm

Which of the following is equal to x?

If  `a = 2 + sqrt(3)`, then find the value of `a - 1/a`.

Simplify:

`(1^3 + 2^3 + 3^3)^(1/2)`

Simplify:

`(3/5)^4 (8/5)^-12 (32/5)^6`

Simplify:

`(9^(1/3) xx 27^(-1/2))/(3^(1/6) xx 3^(- 2/3))`

Which one of the following is a polynomial?

The value of 249² – 248² is ______.

The coefficient of x in the expansion of (x + 3)³ is ______.

If `x/y + y/x = -1 (x, y ≠ 0)`, the value of x³ – y³ is ______.

If `49x^2 - b = (7x + 1/2)(7x - 1/2)`, then the value of b is ______.

If a + b + c = 0, then a³ + b³ + c³ is equal to ______.

Using suitable identity, evaluate the following:

103³

Using suitable identity, evaluate the following:

101 × 102

Using suitable identity, evaluate the following:

999²

Factorise the following: 

4x² + 20x + 25

Factorise the following:

9y² – 66yz + 121z²

Factorise the following:

`(2x + 1/3)^2 - (x - 1/2)^2`

Expand the following:

(4a – b + 2c)²