Question

plz answer it guys l need help​

Answer 1

Answer:

-3(1-i} is the answer

hope it helped

Answer 2

$\displaystyle\huge\red{\underline{\underline{Solution}}}$

FORMULA TO BE IMPLEMENTED

1.

If Z is a complex number then

$|z| = \sqrt{ {x}^{2} + {y}^{2} }$

2.

If Z is in 2nd Quadrant then

$\displaystyle \: \sf{ \: \theta = amp \: z \: } = \pi - \displaystyle \: \sf{ \: { \tan}^{ - 1} \: \bigg| \frac{y}{x} \bigg| }$

EVALUATION

$\sf{ \:z = - 3(1 - i) \: }$

$= \sf{ \: - 3 + 3 i \: }$

Which represents the point ( - 3, 3 ) on complex plane

Which is on 2nd Quadrant

$\sf{ \: Comparing \: with \: z = x + iy \: we \: get\: }$

$\sf{ \: \: x = - 3 \: \: and \: y = 3 \: \: }$

So

$\sf{ \: |z| = \sqrt{ {x}^{2} + {y}^{2} } \: = \sqrt{9 + 9} = \sqrt{18} = 3 \sqrt{2} }$

Again

$\displaystyle \: \sf{ \: \theta = amp \: z \: }$

$= \displaystyle \: \sf{ \: \pi - { \tan}^{ - 1} \: \bigg| \frac{y}{x} \bigg| }$

$=\pi - \displaystyle \: \sf{ \: { \tan}^{ - 1} \: \frac{3}{3} }$

$=\pi - \displaystyle \: \sf{ \: \frac{\pi}{4} }$

$=\displaystyle \: \sf{ \: \frac{3\pi}{4} }$

RESULT

$\sf{ \:modulous \: of \: z \: = 3 \sqrt{2} \: }$

$\displaystyle \: \sf{ \: amp \: z = \frac{3\pi}{4} \: }$