Multiply and simplify the following complex numbers (1+5i) x (-3-i)

Mathematics

1 answer:

Mrrafil [7]3 years ago

4 0

Answer:

2 - 16i

Step-by-step explanation:

$(1 + 5i) \times ( - 3 - i) \\ = 1 \times ( - 3 - i) + 5i \times ( - 3 - i) \\ = - 3 - i - 15i - 5 {i}^{2} \\ = - 3 - 16i - 5( - 1)..( \because \: {i}^{2} = - 1) \\ - 3 - 16i + 5 \\ = 5 - 3 - 16i \\ = 2 - 16i \\ \purple{ \boxed{ \bold{ \therefore \: (1 + 5i) \times ( - 3 - i) = 2 - 16i }}} \\$

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Step-by-step explanation:

We have that to find our $\alpha$ level, that is the subtraction of 1 by the confidence interval divided by 2. So:

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3 years ago

Help with geometry hw

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A and a' are vertical angles, therefore a' = a

We know: The sum of the measures of triangle is always 180°.

Therefore: a' + b + d = 180° → d = 180° - a - b.

d and c are adjacent angles, therefore d + c = 180°

substitute

180° - a - b+ c = 180° |-180°
-a - b + c = 0 |+a |+b
c = a + b