Answer:
Step-by-step explanation: i drew it with marker on the photo
If n is an integer, then cos(n(2<span>π))=1.
Take n=0, cos(2</span>π)=cos(0)=1, n=1, cos(2π)=1, n=2, cos(2(2π))=cos(4<span>π)=cos(0)=1...
If n is not an integer, well, ..... we don't know the value, which depends on the value of n.</span>
Answer:
Plan A: $15 per lawn cutting, plus a flat rate of $20 per month.
Step-by-step explanation:
sorry if I get this wrong, I'm honestly trying to help you find the correct answer. Have a nice day. :)
Recall the double angle identity,
sin(2x) = 2 sin(x) cos(x)
Then we can write
sin(9x) cos(9x) = 1/2 sin(2 • 9x) = 1/2 sin(18x)
Then
∫ sin(9x) cos(9x) dx
= 1/2 ∫ sin(18x) dx
= -1/2 • 1/18 cos(18x) + C
= -1/36 cos(18x) + C
though you could continue with another double angle identity,
cos(2x) = cos²(x) - sin²(x)
to rewrite the antiderivative as
= -1/36 (cos²(9x) - sin²(9x)) + C
= 1/36 (sin²(9x) - cos²(9x)) + C
He messed up in the beginning with the 4.
It's supposed to be
(3 - -4)
(3 + 4)
and not
(3-4)
That's where he messed up.
I find it interesting how he uses Xa Ya and Xb Yb. In my school we use X1 Y1 and X2 Y2.