# RBSE Solutions for Class 11 Maths Chapter 7 Binomial Theorem Ex 7.5

## Rajasthan Board RBSE Class 11 Maths Chapter 7 Binomial Theorem Ex 7.5

Question 1.
If y is two small as compared to x, then prove Solution: Question 2.
If x is too small such that x2 and higher powers are negligible then find the value of following expressions : Solution: Ignoring x2 and terms of higher order     Question 3.
Find the value of:
(i) √3o upto 4 places of decimal
(ii) (1.03)1/3 upto 4 places of decimal
(iii) $$\frac { 1 }{ { (8.16) }^{ 1/3 } }$$ 4 places of decimal
(iv) Cube root of 126 upto 5 places of decimal
Solution :
(i) Value of √30 upto 4 places of decimal = 6 (1 – 0 08333 – 0 – 00347 – 0 – 00029 + …]
= 6 (1 – 0 – 08709] = 6(0 – 91291]
= 5.47746 = 5- 4775 (upto four places).

(ii) Value of (1.03)1/3 upto 4 places of decimal (1.03)1/3= (1 + 0-03)1/3   (iv) Value of cube root of 126 upto 5 places of decimal Cube root of 126 Question 4.
If x is approximately equal to 1, then prove that : Solution:  Question 5.
If p and q are approximately equal, then Prove that Solution:
∵ p and q are approximately equal
∴      p = q + h
where h is too small whose higher order terms can be neglected. 