Answer:
-7/25.
Step-by-step explanation:
From the given point P we see that the hypotenuse = √(3*2 + 4^2) = 5.
So cos θ = 3/5
cos 2 θ = 2 cos^2 θ - 1
= 2 * (3/5)^2 -1
= -7/25.
9514 1404 393
Answer:
81 m
Step-by-step explanation:
Since x is seconds after takeoff, the value of x at takeoff is 0. You are being asked to find H(0).
H(0) = -3(0 -3)^2 +108 = -3(9) +108 = 81
The height of the hovercraft at the time of takeoff is 81 meters.
We need to get x alone, to do that we add 1 to both sides to cancel out the -1 on the right.
-4 = x -1
+1 +1
-3=x
This means x is equal to -3. Hope this helps!