217 × 217 + 183 × 183 = ?
ক
79698
খ
80578
গ
80698
ঘ
81268
ঙ
None of these
সঠিক উত্তর: 80578
= (217 × 217) + (183 × 183)= (217)2 + (183)2
= (200 + 17)2 + (200 - 17)2
= (a + b)2 + (a - b)2
= 2(a2 + b2), where a = 200, b = 17
= 2
= 2
= (2 × 40289)
= 80578
