Answer:
.
Step-by-step explanation:
A) The formula for surface area of a sphere is A = 4*PI*r^2
using 3.14 for PI:
Surface area for Earth = 4 * 3.14 x 3960^2 = 196,960,896 miles^2
Surface area of the moon: 4 * 3.14 * 1080^2 = 14,649,984 miles^2
B)Divide the Surface of the Earth by the moon:
196,960,896 / 14,649,984 = 13.44
The Earths surface is 13.4 times larger than the moon.
C) Multiply the surface of the Earth by 70%:
196,960,896 * 0.70 = 137,872,627.2 million square miles of water.
cos (2x) = cos x
2 cos^2 x -1 = cos x using the double angle formula
2 cos ^2 x -cos x -1 =0
factor
(2 cos x+1) ( cos x -1) = 0
using the zero product property
2 cos x+1 =0 cos x -1 =0
2 cos x = -1 cos x =1
cos x = -1/2 cos x=1
taking the arccos of each side
arccos cos x = arccos (-1/2) arccos cos x = arccos 1
x = 120 degrees x=-120 degrees x=0
remember you get 2 values ( 2nd and 3rd quadrant)
these are the principal values
now we need to add 360
x = 120+ 360n x=-120+ 360n x = 0 + 360n where n is an integer
This is 8). the line is 5 on the y-axis.
(9x3)-9=18
Thisjj bf is the answer enjoy