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# Trig question that requires no trig watch

1. I employed suppositional reasoning and took angle ACB could be a right angle and tried to work out this devil of a problem that way, but it just simply will not concede.
2. Imagine a new point D on the base line that's directly below C, so that ADC and BDC are both right angles.

Suppose the distance CD is 1. What are the distances AD and BD? What is the distance MD?
3. (Original post by Oh, me! Oh, me.)
I employed suppositional reasoning and took angle ACB could be a right angle
Angle ACB cannot be a right angle. If it was, you would have tanA = CotB = 1/CotB, and that clearly isn't the case.

I'd drop a perpendicular from C to AB, meeting it as S say.

Then assign some values.

Let CS = r
Let AM = m
Let MS = d.

Now express the tans you've been given in terms of r,m,d, and also work out what you're looking for, for tan theta, in terms of those.

Edit: Too slow.
4. (Original post by Oh, me! Oh, me.)

I employed suppositional reasoning and took angle ACB could be a right angle and tried to work out this devil of a problem that way, but it just simply will not concede.
C is correct. ASk ifg you cannot see why.

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Updated: October 10, 2013
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