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
Answer:
Andrea bought 3.5 pounds of bananas for a total of $1.24. What was the cost per pound of the bananas?
Step-by-step explanation:
Answer:
1.) 0.948
2.)0.06
3.)8.45
4.).00024
5.)0.03678
6.)2.5
Hope this helps you some!!
Answer:
10%
Step-by-step explanation:
To find this we make a fraction and multiply by 100%
4/40 *100% = 1/10 *100% = 10%
<em>I hope this helps! :)</em>
You know that every 10 minutes the oil moves 25 meters so and in 1 hour there are 60 minutes the equation is 60/10(25) and then you solve
The answer is 150 meters squared
