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
So here is the answer. Initially, Ed's toy cars compared to Pete's toy cars was 5:2. So for every 5 cars that Ed has, Pete has 2. Now that Ed gave 30 cars to Pete. So here it goes. The total number of ratio units is 5+2=7, so each will have an equal number if they both have 3.5 ratio units. That is, if Ed transfers to Pete 1.5 ratio units, their car counts will be equal. Thus 1.5 ratio units = 30 cars, or 1 ratio unit = 20 cars. Therefore, this makes <span> 7*20 cars = 140 cars.
</span>Hope this helps.
Answer:
gof(x) = 3
Step-by-step explanation:
Given that,
f(x) = x+2 and g(x) = x+1
We need to find gof(x).
gof(x) means g[f(x)].
g[f(x)] = g(x +2)
= x+2+1
= x+3
Hence, the value of gof(x) is 3.
Xy + 7<span> = </span>x<span> + y is not a linear </span>equation<span> because the term xy has degree 2. </span>x<span> + 3y</span>2<span> = 6 is not a linear</span>equation<span> because the term 3y</span>2<span> has degree 2. ... </span>x<span> = (constant). is a linear </span>equation<span> but does not</span><span>describe a function</span>
Answer:
24
Step-by-step explanation:
(+24) – (-6) + (-8) – (-2)
= 24 + 6 - 8 + 2
= 24