80 because when u do 10 times 8 it’s 80
De Moivre's theorem uses this general formula z = r(cos α + i<span> sin α) that is where we can have the form a + bi. If the given is raised to a certain number, then the r is raised to the same number while the angles are being multiplied by that number.
For 1) </span>[3cos(27))+isin(27)]^5 we first apply the concept I mentioned above where it becomes
[3^5cos(27*5))+isin(27*5)] and then after simplifying we get, [243 (cos (135) + isin (135))]
it is then further simplified to 243 (-1/ √2) + 243i (1/√2) = -243/√2 + 243/<span>√2 i
and that is the answer.
For 2) </span>[2(cos(40))+isin(40)]^6, we apply the same steps in 1)
[2^6(cos(40*6))+isin(40*6)],
[64(cos(240))+isin(240)] = 64 (-1/2) + 64i (-√3 /2)
And the answer is -32 -32 √3 i
Summary:
1) -243/√2 + 243/√2 i
2)-32 -32 √3 i
Answer:
Hello,
in order to simplify, i have taken the inverses functions
Step-by-step explanation:
![\int\limits^\frac{1}{2} _{-1} {(-2x^2-x+1)} \, dx \\\\=[\frac{-2x^3}{3} -\frac{x^2}{2} +x]^\frac{1}{2} _{-1}\\\\\\=\dfrac{-2-3+12}{24} -\dfrac{-5}{6} \\\\\boxed{=\dfrac{9}{8} =1.25}\\](https://tex.z-dn.net/?f=%5Cint%5Climits%5E%5Cfrac%7B1%7D%7B2%7D%20_%7B-1%7D%20%7B%28-2x%5E2-x%2B1%29%7D%20%5C%2C%20dx%20%5C%5C%5C%5C%3D%5B%5Cfrac%7B-2x%5E3%7D%7B3%7D%20-%5Cfrac%7Bx%5E2%7D%7B2%7D%20%2Bx%5D%5E%5Cfrac%7B1%7D%7B2%7D%20_%7B-1%7D%5C%5C%5C%5C%5C%5C%3D%5Cdfrac%7B-2-3%2B12%7D%7B24%7D%20-%5Cdfrac%7B-5%7D%7B6%7D%20%5C%5C%5C%5C%5Cboxed%7B%3D%5Cdfrac%7B9%7D%7B8%7D%20%3D1.25%7D%5C%5C)
Answer:
120
Step-by-step explanation:
We know that 36 is 30% of total items
So our equation would be 36/? = 30/100
From there we cross multiply so 36x100 = 3600
From there, we divide 3600 by 100
Therefore, your answer is 120
-5x - 6y = -21
5x - y =. 84
-7y = 63
y= -9
-5x = -21 - 54
-5x = -75
x = 15