Sum of Interior Angles of any poligon, where n is the number of sides: =
(n-2) × 180°
---------------------
(7 - 2) * 180° =
5 * 180 =
900°
[d]
Step-by-step explanation:
Remove the parentheses: 15a²-6ab+8a²+20+5ab-31+a²-ab Combine like terms: 24a²-2ab-11
Answer: 24a²-2ab-11
The complex number -7i into trigonometric form is 7 (cos (90) + sin (90) i) and 3 + 3i in trigonometric form is 4.2426 (cos (45) + sin (45) i)
<h3>What is a complex number?</h3>
It is defined as the number which can be written as x+iy where x is the real number or real part of the complex number and y is the imaginary part of the complex number and i is the iota which is nothing but a square root of -1.
We have a complex number shown in the picture:
-7i(3 + 3i)
= -7i
In trigonometric form:
z = 7 (cos (90) + sin (90) i)
= 3 + 3i
z = 4.2426 (cos (45) + sin (45) i)




=21-21i
After converting into the exponential form:

From part (b) and part (c) both results are the same.
Thus, the complex number -7i into trigonometric form is 7 (cos (90) + sin (90) i) and 3 + 3i in trigonometric form is 4.2426 (cos (45) + sin (45) i)
Learn more about the complex number here:
brainly.com/question/10251853
#SPJ1
Answer:
When we have something like:
![\sqrt[n]{x}](https://tex.z-dn.net/?f=%5Csqrt%5Bn%5D%7Bx%7D)
It is called the n-th root of x.
Where x is called the radicand, and n is called the index.
Then the term:
![\sqrt[4]{16}](https://tex.z-dn.net/?f=%5Csqrt%5B4%5D%7B16%7D)
is called the fourth root of 16.
And in this case, we can see that the index is 4, and the radicand is 16.
At the end, we have the question: what is the 4th root of 16?
this is:
![\sqrt[4]{16} = \sqrt[4]{4*4} = \sqrt[4]{2*2*2*2} = 2](https://tex.z-dn.net/?f=%5Csqrt%5B4%5D%7B16%7D%20%3D%20%5Csqrt%5B4%5D%7B4%2A4%7D%20%20%3D%20%5Csqrt%5B4%5D%7B2%2A2%2A2%2A2%7D%20%3D%202)
The 4th root of 16 is equal to 2.
Answer:
9
Step-by-step explanation: