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Can you help me with these trig questions please? :)

1. What is the sector formed by the angle of 240 degrees in a circle with a radius of 5?

(That’s all it says so I’m going to assume that it was asking for the area)

This is my answer: 52.36 square units ( is that correct?).

2. 1/cos(40deg) tan(50deg) - sec(50deg)

I know the answer is 0, but why is it 0?

and

3. why does sin(50deg)/cos(40deg)=1? 



1.area f sector is (area of circle with radius r) * (x/360) x is the angle of the sector, if you did this, your answer is correct


2. 

( tan50)(1/cos40 ) -sec50

= (tan50)(1/sin50) - sec50………………….. nw you would see how it is 0„„„„„, since cos40 = cos(90-50) = sin50 since cos(90-x) = sin x

3 sin 90-x = cosx

so sin 50 = sin(90-40) = cos 40

so cos 40/cos 40 = 1!!

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