Answer:
Step-by-step explanation:
Common ratio r = a₂/a₁ = 16/(-4) = -4
a₄ = a₃(-4) = 256
a₅ = a₄(-4) = -1024
a₆ = a₅(-4) = 4096
Answer:
1) cos (3x)
2) ![\frac{-(1-\sqrt{3})^{2}}{2}](https://tex.z-dn.net/?f=%5Cfrac%7B-%281-%5Csqrt%7B3%7D%29%5E%7B2%7D%7D%7B2%7D)
Step-by-step explanation:
Given expression:
cos(7x)cos(4x)+sin(7x)sin(4x)
By using the trigonometric identity
cos(a)cos(b) + sin(a)sin(b) = cos(a-b)
we have:
cos(7x)cos(4x)+sin(7x)sin(4x) = cos(7x - 4x)
= cos(3x)!
part 2:
tan (-π/12)
by using property tan(-x)= - tan(x)
=-tan(π/12)
= - tan(π/6 / 2)
Using tan(x/2) = ![\sqrt{\frac{1 - cos(x)}{1+cos(x)} }](https://tex.z-dn.net/?f=%5Csqrt%7B%5Cfrac%7B1%20-%20cos%28x%29%7D%7B1%2Bcos%28x%29%7D%20%7D)
= - ![\sqrt{\frac{1 - cos(pi/6)}{1+cos(pi/6)} }](https://tex.z-dn.net/?f=%5Csqrt%7B%5Cfrac%7B1%20-%20cos%28pi%2F6%29%7D%7B1%2Bcos%28pi%2F6%29%7D%20%7D)
cos π/6 = ![\frac{\sqrt{3} }{2}](https://tex.z-dn.net/?f=%5Cfrac%7B%5Csqrt%7B3%7D%20%7D%7B2%7D)
= -![\sqrt{\frac{1-\frac{\sqrt{3} }{2} }{1+\frac{\sqrt{3} }{2} } }](https://tex.z-dn.net/?f=%5Csqrt%7B%5Cfrac%7B1-%5Cfrac%7B%5Csqrt%7B3%7D%20%7D%7B2%7D%20%7D%7B1%2B%5Cfrac%7B%5Csqrt%7B3%7D%20%7D%7B2%7D%20%7D%20%7D)
= - ![\sqrt{7-4\sqrt{3} }](https://tex.z-dn.net/?f=%5Csqrt%7B7-4%5Csqrt%7B3%7D%20%7D)
= - 2+![\sqrt{3}](https://tex.z-dn.net/?f=%5Csqrt%7B3%7D)
= ![-\frac{(1-\sqrt{3}) ^{2} }{2}](https://tex.z-dn.net/?f=-%5Cfrac%7B%281-%5Csqrt%7B3%7D%29%20%5E%7B2%7D%20%7D%7B2%7D)
!
B since they’re all being multiplied by four
Answer: (y-c)/m
Reasoning:
Subtract c from both sides [ y-c=mx+c-c ]
Divide m from both sides [ (y-c)/m=mx/m ]
Take the 5 in 15 and multiply it by 2. Write it. Then take the 5 and multiply it by 1. Write it. On the next line write a zero and then take the 1 multiplied by 2 and then 1 times 1. Here is an example... it's a little complicated to explain but here...
12
15
----
60
120
-------
180
So sorry I can't explain things well...