This is the concept of algebra, to solve the expression we proceed as follows;
cos 2x-cosx=0
cos 2x=cosx
but:
cos 2x+1=2(cos^2x)
thereore;
from:
cos 2x=cos x
adding 1 on both sides we get:
cos 2x+1=cos x+1
2(cos^2x)=cosx+1
suppose;
cos x=a
thus;
2a^2=a+1
a^2-1/2a-1/2=0
solving the above quadratic we get:
a=-0.5 and a=1
when a=-0.5
cosx=-0.5
x=120=2/3π
when x=1
cos x=1
x=0
the answer is:
x=0 or x=2/3π
Answer:
biotbhuvb2tupbpu2
Step-by-step explanation:
Answer:
0.86
Step-by-step explanation:
The z-score we need to make the comparison is given by
where
= the standard deviation established in the study
n = the sample size
and for the Normal distribution N(0,1) we want to find
<em>P(X > -1.0801)
</em>
By using a spreadsheet or the table attached, we find that
P(X > -1.0801) = 0.86
(See picture attached)
I hope this helps you
4.4-7,8
16-7,8
8,2