1 and 2 are equations and 3 is a solution
Answer:
E. -0.723
Since the p value is very high we don't have enough evidence to conclude that the true mean for the lengths is different from 6 cm.
Step-by-step explanation:
Information provided
represent the sample mean for the length
represent the sample standard deviation
sample size
represent the value that we want to test
represent the significance level
t would represent the statistic
represent the p value for the test
System of hypothesis
We need to conduct a hypothesis in order to check if the lathe is in perfect adjustment (6cm), then the system of hypothesis would be:
Null hypothesis:
Alternative hypothesis:
since we don't know the population deviation the statistic is:
(1)
Replacing in formula (1) we got:
E. -0.723
P value
The degrees of freedom are given by:
Since is a two tailed test the p value would be:
Since the p value is very high we don't have enough evidence to conclude that the true mean for the lengths is different from 6 cm.
Answer: Choice A

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Explanation:
Recall that
and
. The connection between tangent and cotangent is simply involving the reciprocal
From this, we can say,

In the second to last step, a pair of sine terms cancel. In the last step, a pair of cosine terms cancel.
All of this shows why
is identical to 
Therefore,
is an identity. In mathematics, an identity is when both sides are the same thing for any allowed input in the domain.
You can visually confirm that
is the same as
by graphing each function (use x instead of alpha). You should note that both curves use the exact same set of points to form them. In other words, one curve is perfectly on top of the other. I recommend making the curves different colors so you can distinguish them a bit better.
I agree. !!!!!!!!!!!!!!!!!!!!!!!!