Find the squares of:
(i) 31, (ii) 72; (iii) 37; (iv) 166.
(i) (a + b)2 = a2 + 2ab + b2
∴312 = (30 + 1)2 = 302 + 2 × 30 × 1 + 12 = 900 + 60 + 1 = 961
(ii) (a + b)2 = a2 + 2ab + b2
∴722 = (70 + 2)2 = 4900 + 280 + 4 = 5184
(iii) (a + b)2 = a2 + 2ab + b2
∴372 = (30 + 7)2 = 900 + 420 + 49 = 1369
(iv) (a + b)2 = a2 + 2ab + b2
∴1662 = (160 + 6)2 = 25600 + 1920 + 36 = 27556