Answer:
Step-by-step explanation:
hello :
the n-ieme term is : An=A1×r^(n-1)
A1 the first term r : the common ratio
in this exercice : A1 =15 r = 1/3 n = 4
A4=15×(1/3)^(4) =15×4^4 =3840
Answee:
We have these two equations:
-2x +4y =-22
2x + 8y -26
We need to try to get the same number multiplying both x or y, I think we can make the 2 of the first equation negative, for that, we multiply all the equation by -1:
2x + 8y =-26 ---- -2x - 8y =26
Now we have this:
-2x +4y = -22
-2x -8y = 26
Now e substract both equations:
-2x - (-2x) +4y -(-8y) = -22-26
12y = -48
Y = -48/12 = -4
And we replace to get x
-2x + 4y = -22
-2x +4*(-4)=-22
-2x - 16 = -22
x= -6/-2 =3
Answer:
cos(400)
Step-by-step explanation:
Useful things:
Cofunction identity: sin(x)=cos(90-x)
Sine and cosine have period of 360 degrees.
So sin(50)=cos(40) by cofunction identity.
Since cosine has period of 360 degrees then cos(40)=cos(360+40).
That simplifies to cos(400).
The one thing you should never do is go faster
