Question

(1+I )^3 express in a+ib form
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Answer 1

$\begin{gathered}\Large{\bold{\pink{\underline{Formula \: Used \::}}}} \end{gathered}$

$\longrightarrow \:(1). \: \boxed { \red{ \:  {(x + y)}^{3} = {x}^{3} + 3 {x}^{2} y + 3x {y}^{2} + {y}^{3} }}$

$\longrightarrow \:(2). \: \boxed{ \green{\bf \:  {i}^{2} = - 1} }$

$\longrightarrow \:(3). \: \boxed{ \blue{\bf \:  {i}^{3} = - i }}$

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$\large\underline\purple{\bold{Solution :- }}$

$\tt \:   \longrightarrow \: {(1 + i)}^{ 3}$

$\tt \:   \longrightarrow \: {1}^{3} + 3 \times {(1)}^{2} \times i + 3 \times (1) \times {(i)}^{2} + {(i)}^{3}$

$\tt \:   \longrightarrow \:1 + 3i - 3 - i$

$\tt \:   \longrightarrow \: - 2 + 2i$

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