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3 years ago

What is the answer for 4i over 3+7i

Mathematics

1 answer:

icang [17]3 years ago

6 0

Answer:

see explanation

Step-by-step explanation:

given $\frac{4i}{3+7i}$

To rationalise multiply the numerator/denominator by the conjugate of the denominator

the conjugate of 3 + 7i is 3 - 7i, hence

$\frac{4i(3-7i)}{(3+7i)(3-7i)}$

distribute the numerator/denominator

= $\frac{12i-28i^2}{9-49i^2}$

[ note that i² = - 1 ]

= $\frac{12i+28}{9+49}$

= $\frac{28+12i}{58}$

= $\frac{28}{58}$ + $\frac{12}{58}$ i

= $\frac{14}{29}$ + $\frac{6}{29}$ i ← in standard form

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Square root of 87 to the nearest 10th

kogti [31]

Answer:

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Step-by-step explanation:

Step 1: Calculate. We calculate the square root of 87 to be: √87 = 9.32737905308882.

Step 2: Reduce. 9.32.

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3 years ago

In ΔABC, the lengths of a, b, and c are 22.5 centimeters, 18 centimeters, and 13.6 centimeters, respectively.

Irina-Kira [14]

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We can apply the same reasoning for finding the value of ∠B as shown.

$B = cos^{-1} (\frac{a^{2}+c^{2}-b^{2}}{2ac})$

Plugging in the values of the sides (see image attached) from the given. It will now be straightforward to compute for ∠B and ∠C.

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Answer: ∠C = 37.19° and ∠B = 53.13°

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3 years ago

Read 2 more answers

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