Question

Evaluate by using suitable identities: (i) 297 × 303 (ii) 102 x 104​

Answer 1

$\huge\bold{\gray{\sf{Answer:}}}$

Explanation:

$297 \times 303$

Here ,this identity is used:

$\bold{\boxed{(x + y)(x - y) = {x}^{2} - {y}^{2} }}$

$= > (300 - 3)(300 + 3)$

$= > {(300)}^{2} - {(3)}^{2} = 90000 - 9$

$\bold{= 89991}$

$(ii)102 \times 104$

Here,this identity is used:

$\bold{\boxed{(x +a)(x + b) = {x}^{2} + (a + b)x + ab}}$

$(100 + 2)(10 0 + 4) = {x}^{2} + (a + b)x + ab$

$= {(100)}^{2} + (2 + 4)100 + 2 \times 4$

$= 10000 + 600 + 8 = 10000 + 608$

$\bold{ = 10608}$