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3 years ago

What is the answer to (3-4i)(5+6i)

Mathematics

2 answers:

densk [106]3 years ago

4 0

Answer:

39 - 2i

Step-by-step explanation:

First, you need to FOIL the equation:

$(3 - 4i)(5 + 6i) \\15 + 18i - 20i - 24i^2\\15 - 2i - 24(-1)\\15 - 2i + 24\\39 - 2i\\$

Remember that $i^2$ equals -1.

Therefore, the answer to this question is 39 - 2i

I hope this helps!!

- Kay :)

gulaghasi [49]3 years ago

3 0

(3-4i)(5+6i)

15+18i-20i-24i^2

15+18i-20i+24=

39-2i

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a. We want to test $H_{0}: \mu_{1}-\mu_{2} = 0$ vs $H_{1}: \mu_{1}-\mu_{2} \neq 0$ (two-tailed alternative).

The test statistic is $T = \frac{\bar{x}_{1} - \bar{x}_{2}-0}{S_{p}\sqrt{1/n_{1}+1/n_{2}}}$ and the observed value is $t_{0} = \frac{2.04 - 2.07}{(0.01246)(0.3)} = -8.0257$ . T has a Student's t distribution with 20 + 25 - 2 = 43 df.

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$-0.03\pm(2.0167)(0.012459)(0.3)$ , i.e.,

(-0.0225, -0.0375)

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