Find a solution to the equation if possible.(adsbygoogle = window.adsbygoogle || []).push({});

Give the answer in exact form and in decimal form.

1 = 8cos(2x + 1) - 3

1 = 8tan(2x + 1) - 3

I don't know how to do this one.. but I know how to do the simpler ones like..

2 = 5sin(3x)

2/5 = sin(3x)

(sin^{-1}(2/5)) / 3 = 0.137172

Those are easier... but the one i've said before...

1 = 8cos(2x + 1) - 3 is tough..

1/8 = cos(2x + 1) - 3

3.125 = cos(2x + 1)

{[cos^{-1}(3.125)] / 2} - 1

Is this correct thus far, and if it is... cos^{-1}(3.125) is nonreal. So I guess there are no solutions...

How about this one?

1 = 8tan(2x + 1) - 3

1/8 = tan(2x + 1) - 3

3.125 = tan(2x + 1)

{[tan^{-1}(3.125)] / 2} - 1 = -0.369453

But, the right side doesn't evaluate to 1 when you plug -0.369453 in for x

I don't know where to go with these.

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# Homework Help: Trig Equation

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