MHB Trigonometric function values of quadrantal angles

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The discussion revolves around the calculation of 7 cot 270° + 4 csc 90°, highlighting confusion due to a domain error encountered on a calculator. It is clarified that tan(270°) is undefined, which leads to the error when attempting to compute cotangent. The suggestion is made to use the identity 7*cos(270°)/sin(270°) as an alternative method for calculation. Additionally, it is noted that a calculator may not be necessary for solving this problem. Understanding the properties of trigonometric functions at quadrantal angles is essential for resolving such issues.
bgb
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I can't seem to solve 7 cot 270° + 4 csc 90°
I don't know whether I'm entering something in my calculator wrong (could've sworn I was doing it right earlier) or if there just isn't an answer.

In my calculator, I enter 7/tan(270°)+4/sin(90°) and it gives me a domain error.
 
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bgb said:
I can't seem to solve 7 cot 270° + 4 csc 90°
I don't know whether I'm entering something in my calculator wrong (could've sworn I was doing it right earlier) or if there just isn't an answer.

In my calculator, I enter 7/tan(270°)+4/sin(90°) and it gives me a domain error.

The reason is because tan(270°) is undefined.

You really shouldn't need a calculator for this, but if you really do, try entering as 7*cos(270°)/sin(270°).
 
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