evaluate using expansion of (a+b)2 or (a-b)2. (415)2 (188)2 (9.4)2 (20.7)2

Asked by rainikita525 | 8th Apr, 2020, 11:07: AM

Expert Answer:

(415)2
= (400+15)2
= (400)2 + 2 x 400 x 15 + (15)2
= 160000 + 12000 + 225
= 172225
 
 
(188)2
= (200 - 12)2
= (200)2 - 2 x 200 x 12 + (12)2
= 40000 - 4800 + 144
= 40144 - 4800
= 35344
 
 
(9.4)2
= (9 + 0.4)2
= 92 + 2 x 9 x 0.4 + (0.4)2
= 81 + 7.2 + 0.16
= 88.36
 
 
(20.7)2
= (20 + 0.7)2
= (20)2 + 2 x 20 x 0.7 + (0.7)2
= 400 + 28 + 0.49
= 428.49

Answered by Renu Varma | 8th Apr, 2020, 11:23: AM