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# Trigonometry Mathematics GCSE Cos(x)= -0.4 watch

1. Im using a worksheet and the question is

COS(x)= -0.4

and the answers are x = 92.3º and 267.7º

I don't understand how the worksheet has these answers and

Cos^-1 (-0.4) = 113.58
2. (Original post by chloewhitexox)
Im using a worksheet and the question is

COS(x)= -0.4

and the answers are x = 92.3º and 267.7º

I don't understand how the worksheet has these answers and

Cos^-1 (-0.4) = 113.58
it is 113.58 degrees. Worksheet's got error i think.
3. pretty sure it's right. imagine the graph of y = cosx and y = -0.4. they intersect at two points.
4. (Original post by chloewhitexox)
Im using a worksheet and the question is

COS(x)= -0.4

and the answers are x = 92.3º and 267.7º

I don't understand how the worksheet has these answers and

Cos^-1 (-0.4) = 113.58
5. (Original post by Mathchester)
The worksheet is in degrees "Give answers between 0-360 Degrees"
6. (Original post by Mathchester)

The worksheet is in degrees

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