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:
1. 6pi or 18.84cm
2. 20pi or 62.8cm
3. 13pi or 40.82cm
4. 9.5pi or 29.83cm
5. You calculate the circumference of a circle with the expression 2pi(r). r stands for the radius. You can also use pi(d), or pi x diameter.
7. You would use 2pi(r) to find the circumference of a circle when given the value of the circle's radius.
8. You would use pi(d) to find the circumference of a circle when given the value of the circle's diameter.
If George completed 3/5 of work in 9 days, it means that he needs 3 days to finish 1/5th of the work.
The remaining part is 2/5 because 1-3/5=2/5. 2/5 is also 6/15
From this, how much did George do? in the first 3 days he did 1/5th and then one more day was left, during which he did 1/5/3=1/15th.
So he did in total 1/15+1/5=1/15+3/15=4/15.
this means that Paul did the rest of 6/15, so Paul did 6/15-4/15=2/15.
So we know that he does 2/15 in 4 days, which means that every two days he can do 1/15 of the work
so he would need 15 times 2 days to finish the work - 30 days!
1 bag per 5 minutes.
If you divide 15(total amount of min) by 3(bags of popcorn you popped) you will see you popped 1 bag per 5 minutes.
Now its say per minutes, then, you will have to say 1/5 bag per minutes.
Answer:
M= 15 degrees N= 15 degrees
Step-by-step explanation:
Right triangles are always 90 degrees so 90-60=30
since theres 2 sides you have to split 30 in 2 so 30 divided by 2 equals 15