Answer:
3inches each month or 36inches in a year
Step-by-step explanation:
We will use double angle identities:
cos (5x ) = sin (10x )
cos (5x ) = 2 cos (5x ) sin ( 5x )
cos ( 5 x) - 2 cos ( 5 x ) sin ( 5x ) = 0
cos ( 5 x ) · [ 1 - 2 sin (5 x) ] = 0
cos ( 5 x ) = 0 or : 1 - 2 sin (5 x) = 0
5 x = π/2 +kπ, k∈Z sin (5 x) = 1/2
x1 = π/10 + kπ/5 5 x = π/6+2kπ , k∈ Z
5 x = 5π/6 +2kπ , k∈ Z
x 2 = π/30 +2kπ/5
x 3 = π/9 + 2kπ/5
Answer:
B). 37.68 feet.
Step-by-step explanation:
Circumference = diameter * π
= 12 * π
= 37.68 feet.
The remaining area that the grass will cover will be given by:
Area=[area of rectangle]-[area of the triangle]
area of rectangle will be:
A1=length*width
=20*8
=160 square feet
The area of the triangle will be:
A2=1/2absin theta
since the triangle is equilateral, all the angles are equal and the size of each angle is 60°. Thus the area will be:
A2=1/2*5*5sin 60
=18.3
thus the remaining area of the grass will be:
Area=160-18.3
=149.7 square feet