Trigonometric function values of quadrantal angles

[bgb]

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.

 

[Prove It]

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°).