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:
104 units
Step-by-step explanation:
Given
Shape: Rhombus
Required
Determine the perimeter
The given parameter are the diagonals of the rhombus.
The perimeter (from diagonals) is calculated as thus:
Substitute values for JL and KM
<em>Hence, the perimeter is 104 units</em>
The volume of a cone is 1/3 pi r^2 h, so plug this in to get the answer
Answer:
Step-by-step explanation:
y = (-1/2)x + 4 is the equation of a straight line with y-intercept (0, 4) and slope -1/2.
To graph this, first plot the y-intercept (0, 4).
Recall that slope m = rise / run, and notice that the slope in this particular case is -1/2 = rise / run, or rise = -1 and run = 2.
Starting with your pencil point on (0, 4), move the point 2 units to the right (run = 2), arriving at (2, 4). Next, move your pencil point 1 unit down, to (2, 3).
Draw a straight line through (0, 4) and (2, 3).
Answer:
Step-by-step explanation:
1) y intercept is 0
2) y intercept is 1
3) y intercept is -4
4) y intercept is 4
5) y intercept is 5
6) y intercept is 0
7) y intercept is 5
8) y intercept is 4
