Answer:
Step-by-step explanation:
Use the half angle identity for cosine:
cos(x/2)=+ or - sqrt(1+cos(x))/sqrt(2)
I'm going to figure out the sign part first for cos(x/2)...
so x is in third quadrant which puts x between 180 and 270
if we half x, x/2 this puts us between 90 and 135 (that's the second quadrant)
cosine is negative in the second quadrant
so we know that
cos(x/2)=-sqrt(1+cos(x))/sqrt(2)
Now we need cos(x)... since we are in the third quadrant cos(x) is negative...
If you draw a reference triangle sin(x)=3/5 you should see that cos(x)=4/5 ... but again cos(x)=-4/5 since we are in the third quadrant.
So let's plug it in:
cos(x/2)=-sqrt(1+4/5)/sqrt(2)
No one likes compound fractions (mini-fractions inside bigger fractions)
Multiply top and bottom inside the square roots by 5.
cos(x/2)=-sqrt(5+4)/sqrt(10)
cos(x/2)=-sqrt(9)/sqrt(10)
cos(x/2)=-3/sqrt(10)
Rationalize the denominator
cos(x/2)=-3sqrt(10)/10
Five months
Reason: graph y=35.75x+75 and y=17.95x+164 and they connect in the middle of 253-254 for month 5
Answer:
f(x)=x-24
Step-by-step explanation:
It is decreasing by 24. Hope this helps!
Hi there!
Let's start by replacing "a number" by the letter "x" so that we can do an equation and isolate "x" to find your answer :
(x - 
) + 
= -7
subtract on each side of the equation
x - = -8.25
add on each side of the equation
x = -7.5
-7.5 - 3/4 = -8.25
-8.25 + 5/4 = <u>-7</u>
So your answer is : Three-fourths was subtracted from -7.5, and then 5/4 was added to the result. The sum was -7.
There you go! I really hope this helped, if there's anything just let me know! :)
$72 - $30 = $42
It increased $42.
Now take this number and divide by the original number (first):
42 ÷ 30
This is 1.4, let's convert this to a percentage.
We now times it by 100
1.4 × 100
The answer is 140%
