This is true. The word equal in equality will help, each side of the equation in the in(equal)ity should be done the same.
Answer: f(120°) = (√3) + 1/2
Step-by-step explanation:
i will solve it with notable relations, because using a calculator is cutting steps.
f(120°) = 2*sin(120°) + cos(120°)
=2*sin(90° + 30°) + cos(90° + 30°)
here we can use the relations
cos(a + b) = cos(a)*cos(b) - sin(a)*sin(b)
sin(a + b) = cos(a)*sin(b) + cos(b)*sin(a)
then we have
f(120°) = 2*( cos(90°)*sin(30°) + cos(30°)*sin(90°)) + cos(90°)*cos(30°) - sin(90°)*sin(30°)
and
cos(90°) = 0
sin(90°) = 1
cos(30°) = (√3)/2
sin(30°) = 1/2
We replace those values in the equation and get:
f(120°) = 2*( 0 + (√3)/2) + 0 + 1/2 = (√3) + 1/2
You need to make a series of equations from what you are given first. I am going to use the first letter of each of the names to represent the length of that persons wire.
1/2s=2/5d
3c=s
s+d+c=6 ft
Okay. Now you can combine the first two equations knowing what s equals:
1/2(3c)=2/5d
d=15c/4
Now you have d=15c/4 and s=3c, so you can replace d and s in the third equation.
3c+15c/4+c=6
Then solve for c and plug it into the equation 3c=s to find the length of sarah's wire.
the function f(x) is increasing.
looking at the domain -2 < x < -1, we can see that the function f(x) = 2^x (labeled in blue) has an increasing slope.
