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:
44
Step-by-step explanation:
ieubedhjdidieuehehbebeheiduudueuehhehehe
Let be Z the money ;
We have ( 40 / 100 ) x Z = $85 ;
( 4 / 10 ) x Z = $85 ;
( 2 / 5 ) x Z = $85 ;
Z = $( 85 x 5 ) ÷ 3 ;
Z = $425 ÷ 3 ;
Z = $141,66 ≈ $142 ;
Answer:
x=11
Step-by-step explanation:
7x-9-4(x-1)=28
7x-9-4x+4=28
3x-5=28
3x=33
x=11
Answer:
C,
Step-by-step explanation:
A and D is incorrect because they are negative correlation
and B is incorrect because a correction of 0.95 means all values are close to each other, but B values are scattered much more that C values
so answer C