If a = 2, b = -2, find the value of:
(i) a² + b²
(ii) a² + ab + b²
(iii) a² - b²

Solution:

Let us find the value of given expressions by substituting the given value of a and b.

(i) a² + b²

= (2)² + (-2)²

= 4 + 4

= 8 is the required value.

(ii) a² + ab + b²

= (2)² + 2 × (-2) + (-2)²

= 4 - 4 + 4

= 4 is the required value.

(iii) a² - b²

= (2)² - (-2)²

= 4 - 4

= 0 is the required value.

☛ Check: NCERT Solutions for Class 7 Maths Chapter 12

Video Solution:

If a = 2, b = -2, find the value of: (i) a² + b² (ii) a² + ab + b² (iii) a² - b²

Maths NCERT Solutions Class 7 Chapter 12 Exercise 12.3 Question 4

Summary:

If a = 2, b = -2, the value of: (i) a² + b² = 8 (ii) a² + ab + b² = 4 (iii) a² - b² = 0

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