Answer:

Step-by-step explanation:
Hello,

Hope this helps.
Do not hesitate if you need further explanation.
Thank you
(z + 6) / 3 = 2z / 4
this is a proportion, so we cross multiply
(3)(2z) = 4(z + 6)
6z = 4z + 24
6z - 4z = 24
2z = 24
z = 24/2
z = 12 <==
Answer:
A sample size of at least 737 specimens is required.
Step-by-step explanation:
We have that to find our
level, that is the subtraction of 1 by the confidence interval divided by 2. So:

Now, we have to find z in the Ztable as such z has a pvalue of
.
So it is z with a pvalue of
, so 
Now, find the width M as such

In which
is the standard deviation of the population and n is the size of the sample.
In this problem, we have that:

So:





A sample size of at least 737 specimens is required.
Answer:
sin⁴x - sin²x = cos⁴x - cos²x
Solve the right hand side of the equation
That's
sin⁴x - sin²x
<u>From trigonometric identities</u>
<h3>
sin²x = 1 - cos²x</h3>
So we have
sin⁴x - ( 1 - cos²x)
sin⁴x - 1 + cos²x
sin⁴x = ( sin²x)(sin²x)
That is
( sin²x)(sin²x)
So we have
( 1 - cos²x)(1 - cos²x) - 1 + cos²x
<u>Expand</u>
1 - cos²x - cos²x + cos⁴x - 1 + cos²x
1 - 2cos²x + cos⁴x - 1 + cos²x
<u>Group like terms</u>
That's
cos⁴x - 2cos²x + cos²x + 1 - 1
<u>Simplify</u>
We have the final answer as
<h3>cos⁴x - cos²x</h3>
So we have
<h3>cos⁴x - cos²x = cos⁴x - cos²x</h3>
Since the right hand side is equal to the left hand side the identity is true
Hope this helps you
Answer:
41,042,523,288 It is even.
Step-by-step explanation:
To tell whether a number is even or odd, look at the number in the ones place. That single number will tell you whether the entire number is odd or even. An even number ends in 0, 2, 4, 6, or 8. An odd number ends in 1, 3, 5, 7, or 9.