Use the product (a + b)(a - b) = a2−b2 to evaluate : (i) 21×19 (ii) – InterviewSolution

1.

Use the product (a + b)(a - b) = a2−b2 to evaluate : (i) 21×19 (ii) 33×27 (iii) 103×97 (iv) 9.8×10.2 (v) 7.7×8.3 (vi) 4.6×5.4

Answer»

Use the product (a + b)(a - b) = $a^{2} - b^{2}$ to evaluate :

(i) $21 \times 19$

(ii) $33 \times 27$

(iii) $103 \times 97$

(iv) $9.8 \times 10.2$

(v) $7.7 \times 8.3$

(vi) $4.6 \times 5.4$

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