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xobikinibabiixo
Apr 26, 2007, 12:10 PM
this one has got me stumped can anyone help me please:confused:

Verify:

_1_ - __cosB__= tanB
cosB 1+sinB

galactus
Apr 26, 2007, 12:18 PM
Hello:

\frac{1}{cosx}-\frac{cosx}{1+sinx}

Multiply the right portion by 1-sinx

\frac{1}{cosx}-\frac{cosx}{1+sinx}\cdot\frac{1-sinx}{1-sinx}

\frac{1}{cosx}-\left(\frac{cosx-cosxsinx}{1-sin^{2}x}\right)

Inside the parentheses, factor cosx out of the numerator. Then, notice what 1-sin^{2}x is equal to?

Now continue?

galactus
Apr 26, 2007, 06:49 PM
Emland agrees: Ug, the above is what I envision Hell to be like.

No, that's only the first level. As one descends further into Dante's mathematical inferno, one finds Differential Geometry, Group Theory, Algebraic Topology, etc. When sinful mathophobes get there, they are in for an eternity of unrelenting math.
They are going to be made to rationalize denominators and simplify radical expressions FOREVER. ***gives maniacal laugh and twirls moustache*** :D