I’ll what is this language
Answer:
The sample size required is at least 171
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 margin of error M as such

In which
is the standard deviation of the population and n is the size of the sample.
What sample size is required?
A samle size of at least n is required, in which n is found when 
So






Rouding up
The sample size required is at least 171
Answer:
cos2t/cos²t
Step-by-step explanation:
Here the given trigonometric expression to us is ,
We can write the numerator as ,
Recall the identity ,
Using this we have ,
Again , as we know that ,
Therefore we can rewrite it as ,
Again using the first identity mentioned above ,
Or else we can also write it using ,
Therefore ,
And we are done !
Additional info :-
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We can rewrite cos 2x as ,
As we know that ,
So that ,
On simplifying,
Hence,

1 3/4 is greater than 0.75 because 1 3/4 is 1.75 and it is greater than 0.75