You have the following expression:
To verify the identity, you have that the left side of the equation becomes:
(1 + cosx)(1 - cosx) = (1 - cos^2 x)
because of the product of an expression by its conjugate result in a difference of squares. Or simplfy by expanding the factors and simplying.
Next, you have:
1 - cos^2 x = sin^2 x
because the Pythagorean identity.
Then, the identity is verified.
Answer:
V = 1206.3
Step-by-step explanation:
This shape is made up of a cylinder on the bottom and a cone on the top. We'll find the volumes of these shapes separately and then add them together.
Volume of a cylinder = area (of the base) x height
Substitute in the formula for the area of a circle.
V(cylinder) = x h
Substitute in the values for the radius (8) and height (4)
V(cylinder) = x
x 4
Evaluate using a calculator
V(cylinder) = 804.2477
To the nearest tenth, V(cylinder) = 804.2
Volume of a cone = . This is the area of the circular part of the cone (
), multiplied by the height from the point to the base, all divided by 3.
Substitute in the values for the radius of the circle (8) and the height (6)
V(cone) = (On the top it's
x
x 6)
Evaluate using a calculator
V(cone) = 402.1239
To the nearest tenth, V(cone) = 402.1
Total volume = V(cylinder) + V(cone)
= 804.2 + 402.1
= 1206.3