Let's check.
x = 5π/24
4x = 5π/6
cos 4x = cos(5π/6) = cos 150° = -√3/2
cos² 4x = (-√3/2)^2 = 3/4
4 cos² 4x -3 = 4 (3/4) - 3 = 0
Answer: TRUE
Answer:
I pretty sure the answer is 171,000 . but if i'm wrong someone can correct me
Step-by-step explanation:
Answer:
See attachment
Step-by-step explanation:
The given inequality is 
By the definition of the absolute value function, we obtain the compound inequality.
When we simplify we get:
The graph for the solution set is shown in the attachment
Answer:
Explanation:
To simplify a polynomial, we have to do two things: 1) combine like terms, and 2) rearrange the terms so that they're written in descending order of exponent.
First, we combine like terms, which requires us to identify the terms that can be added or subtracted from each other. Like terms always have the same variable (with the same exponent) attached to them. For example, you can add 1 "x-squared" to 2 "x-squareds" and get 3 "x-squareds", but 1 "x-squared" plus an "x" can't be combined because they're not like terms.
Let's identify some like terms below.
f(x)=−4x+3x2−7+9x−12x2−5x4
Here you can see that -4x and 9x are like terms. When we combine (add) -4x and 9x, we get 5x. So let's write 5x instead:
f(x)=5x+3x2−7−12x2−5x4
Let's do the same thing with the x-squared terms:
f(x)=5x+3x2−7−12x2−5x4
f(x)=5x−9x2−7−5x4
Now there are no like terms left. Our last step is to organize the terms so that x is written in descending power:
f(x)=−5x4−9x2+5x−7
Step-by-step explanation:
Answer:
x = 8, y = 2
Step-by-step explanation:
Multiply the second equation by -2:
x + 6y = 20
-2x - 6y = -28
Add the equations and simplify:
-x = -8
x = 8
Plug x = 8 back into the first equation and solve for y:
8 + 6y = 20
6y = 12
y = 2
