simplify (3+9i)^2

Solution

simplify

(3 + 9 i)^{2}

- 72 + 54 i

Solution steps

(3 + 9 i)^{2}

Apply Perfect Square Formula:

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

(3 + 9 i)^{2} = 3^{2} + 2 \cdot 3 \cdot 9 i + (9 i)^{2}

= 3^{2} + 2 \cdot 3 \cdot 9 i + (9 i)^{2}

Simplify

3^{2} + 2 \cdot 3 \cdot 9 i + (9 i)^{2} : 54 i - 72

= 54 i - 72

Rewrite in standard complex form:

- 72 + 54 i

= - 72 + 54 i

\frac{x ^{2} - 4 x - 5}{x ^{2} - 2 x - 15} \cdot \frac{7 x}{7 x}

3 + \frac{3}{2}

(2 n^{4})^{3}

x^{3} - 3 x^{2} + 3 x

\frac{4 x ^{2} - 9}{8 x ^{3} - 27}