Example 20 - Chapter 1 Class 9 Number Systems (Term 1)

Rationalising denominator of irrational number

Add (3√2+7√3) and (√2−5√3)

Divide 5√11 by 3√33

Multiply 2√15 by 7√5

Simplify (√5+√7)^2

Simplify (√4−√13)(√4+√13)

Simplify (9−√3)(9+√3)

Simplify (3√5−5√2)(4√5+3√2)

Rationalise the denominator of 8/√7

Rationalise the denominator of 1/((8 + 5√2))

Simplify (7√3)/(√10 + √3)−(2√5)/(√6 + √5)−(3√2)/(√15 + 3√2)

Multiple Choice Questions - Chapter 1 Class 9 Maths

Example 17

If a and b are rational numbers and (√11 − √7)/(√11 + √7) = a – b√77, find the value of a and b

Example 18

Find the values of a and b if (7 + 3√5)/(3 + √5) – (7 − 3√5)/(3 − √5) = a+√5 b

If x = 1/(2 − √3), find the value of x^3 − 2x^2 − 7x + 5

Ex 1.5, 5 (i)

If a = 5 + 2√6 and b = 1/a, then what will be the value of a^2+b^2 ?

Example 19

Example 20 Important You are here