Question

29. Using (a - b) = (a? + b2 - 2ab), evaluate :
(i) (97)
(ii) (992)
(iii) (9.98)​

Answer 1

Answer:

a=100 b= 3

(100_3)^2 by using identity .

10000 +9-2×100×3

10000+9_600

10009-600

9409 ans.

Step-by-step explanation:

I have solved one you should solved by this method

Answer 2

Step-by-step explanation:

29.(i)

$97 = (100 - 3) \\ = ( {100}^{2} + {3}^{2} - 2 \times 100 \times 3) \\ = 10000 + 9 - 600 \\ = 9409$

29.(ii)

$992 = (1000 - 8) \\ = ( {1000}^{2} + {8}^{2} - 2 \times 1000 \times 8) \\ = 1000000 + 64 - 16000 \\ = 984064$

29.(iii)

$9.98 = (10 - 0.02) \\ = ( {10}^{2} + {0.02}^{2} - 2 \times 10 \times 0.02) \\ = 100 + 0.0004 - 0.4 \\ = 99.6004$