Q7 of 157 Page 22

If a + b = 5 and a – b = 4, find a2 + b2 and ab.

Given: a + b = 5 and a + b = 5


Using (a– b)2 = a2 + b2 – 2a×b and (a+ b)2 = a2 + b2 + 2a×b






Similarly,





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(a – b) (a + b) + (b – c) (b + c) + (c – a)(c + a) = 0

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i. If the values of a + b and ab are 12 and 32 respectively, find the values of a2 + b2 and (a – b)2.

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If (x + a) (x + b) = x2 – 5x – 300, find the values of a2 + b2.