Question

EXPAND
$(x + 4 ){}^{3}$
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Answer 1

Question

$\sf \underline \color{aqua}{Expand}$

(i) (X+4)³

solution

we know the identity

${ \underline{ \boxed{\sf \color{grey}{ {(a + b})^{3} = {a}^{3} + {b}^{3} + 3 {a}^{2} b + 3a {b}^{2} }}}}$

subsitute the values in the identity

$\sf{ \implies(x+4)³ } \\ \\ \sf{ \implies {x}^{3} + 64+ 3× x²× 4 + 3 × x× 4²} \\ \\ \sf{\implies \: {x}^{3} +64 +12x²+48x}$

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More to know !!

$\sf{✒(a+b) ²= a²+b²+2ab} \\ \\\sf{✒(a-b)² = a²+b² -2ab} \\ \\ \sf{✒ (a-b)³ = a³-b³ +3ab² -3a²b} \\ \\ \sf{✒ a²-b² = (a+b) (a-b)} \\ \\ \sf{✒a³ +b³= (a+b) (a²+ b²-ab)}$

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