Answer:
Solution : 
Step-by-step explanation:
![-3\left[\cos \left(\frac{-\pi }{4}\right)+i\sin \left(\frac{-\pi \:}{4}\right)\right]\:\div \:2\sqrt{2}\left[\cos \left(\frac{-\pi \:\:}{2}\right)+i\sin \left(\frac{-\pi \:\:\:}{2}\right)\right]](https://tex.z-dn.net/?f=-3%5Cleft%5B%5Ccos%20%5Cleft%28%5Cfrac%7B-%5Cpi%20%7D%7B4%7D%5Cright%29%2Bi%5Csin%20%5Cleft%28%5Cfrac%7B-%5Cpi%20%5C%3A%7D%7B4%7D%5Cright%29%5Cright%5D%5C%3A%5Cdiv%20%5C%3A2%5Csqrt%7B2%7D%5Cleft%5B%5Ccos%20%5Cleft%28%5Cfrac%7B-%5Cpi%20%5C%3A%5C%3A%7D%7B2%7D%5Cright%29%2Bi%5Csin%20%5Cleft%28%5Cfrac%7B-%5Cpi%20%5C%3A%5C%3A%5C%3A%7D%7B2%7D%5Cright%29%5Cright%5D)
Let's apply trivial identities here. We know that cos(-π / 4) = √2 / 2, sin(-π / 4) = - √2 / 2, cos(-π / 2) = 0, sin(-π / 2) = - 1. Let's substitute those values,
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As you can see your solution is the last option.
Answer:
x = 6
Step-by-step explanation:
PR / RQ = P'R' / R'Q'
x / 9 = 10 / 15
cross-multiply:
15x = 90
x = 90/15
x = 6
Answer:
x = 51
Step-by-step explanation:
The figure shown is a pentagon
The angles in a pentagon add up to equal 540
Which means that 77 + 107 + 156 + 149 + x = 540
^ ( note that we just created an equation that we can
use to solve for x )
We then solve for x using that equation
77 + 107 + 156 + 149 + x = 540
step 1 combine like terms
77 + 107 + 156 + 149 = 489
we now have 489 + x = 540
step 2 subtract 489 from each side
489 - 489 cancels out
540 - 489 = 51
we're left with x = 51
Answer:
C
Step-by-step explanation:
I'm not sure if my picture made since because I'm not the best at drawing but that's how I'd explain it
