simplify (2-3zi)^2

Solution

simplify

(2 - 3 z i)^{2}

(4 - 9 z^{2}) - 12 z i

Solution steps

(2 - 3 z i)^{2}

Apply Perfect Square Formula:

(a - b)^{2} = a^{2} - 2 ab + b^{2}

(2 - 3 z i)^{2} = 2^{2} - 2 \cdot 2 \cdot 3 z i + (3 z i)^{2}

= 2^{2} - 2 \cdot 2 \cdot 3 z i + (3 z i)^{2}

2^{2} = 4

- 2 \cdot 2 \cdot 3 z i = - 12 z i

(3 z i)^{2} = - 9 z^{2}

= 4 - 12 z i - 9 z^{2}

Rewrite in standard complex form:

(4 - 9 z^{2}) - 12 z i

= (4 - 9 z^{2}) - 12 z i

P_{1} (10, - 3) P_{2} (14, - 7)

\frac{e ^{- s}}{s ( s ^{2} + 4 )}

(\frac{3 x}{2} - \frac{y}{3}) (\frac{3 x}{2} + \frac{y}{3})

\frac{4}{( x ^{2} - 9 ) ^{2}}

\frac{x ^{2} + x - 2}{( 2 x ^{2} - 1 ) ( x + 1 )}