Why Are My Trig Ratios csc and sec Incorrect for (7π)/4?

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The discussion centers on finding the trigonometric ratios for (7π)/4, where the user correctly calculated sin, cos, and tan but struggled with csc and sec. The user initially derived csc as 2/(-√2) and sec as 2/(√2), but the correct values are csc = -√2 and sec = √2. The confusion arises from the need to rationalize the denominators in the user’s calculations. It is emphasized that csc is indeed the reciprocal of sin and sec is the reciprocal of cos, but proper simplification leads to the correct results. Understanding the rationalization process clarifies the discrepancy in the values.
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Homework Statement


The question states to find the primary trig ratios for (7π)/4

Homework Equations

The Attempt at a Solution


I got
sin= (-√2)/2
cos=(√2)/2
tan= -1
csc= 2/(-√2)
sec= 2/(√2)
cot= -1

I got all of them correct except for csc and sec, and I am unsure why the solutions are telling me
csc = -√2
sec = √2
I thought my original answers were correct because csc is reciprocal of sin and sec is reciprocal of cos.
Can someone help me make sense of this?
 
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Write ##2= \sqrt{2}\,\cdot\,\sqrt{2}## and cancel one root factor.
 
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Veronica_Oles said:

Homework Statement


The question states to find the primary trig ratios for (7π)/4

Homework Equations

The Attempt at a Solution


I got
sin= (-√2)/2
cos=(√2)/2
tan= -1
csc= 2/(-√2)
sec= 2/(√2)
cot= -1

I got all of them correct except for csc and sec, and I am unsure why the solutions are telling me
csc = -√2
sec = √2
I thought my original answers were correct because csc is reciprocal of sin and sec is reciprocal of cos.
Can someone help me make sense of this?
Rationalize the denominators.
 
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