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Elijah the Wood
Nov6-04, 02:39 PM
I'm retarded...any help would be much congratulated...and i have two problems that are bugging me fiercing

Prove the given identity:

1)
tan(x)-sin(x)/2tan(x) = sin^2(x/2)



2)
sin2x = 1 / tanx + cot2x

Sirus
Nov6-04, 03:00 PM
Please show us what you have tried so far.

math_fortress
Nov6-04, 03:43 PM
Hmmm..that is tough...
I'm actually having trouble w/ questions similar to this too

math_fortress
Nov6-04, 04:03 PM
on number 2...wouldn't you try to get both sides equal to "sin2x"?

Elijah the Wood
Nov7-04, 10:11 AM
1)
tan(x)-sin(x)/2tan(x) = sin^2(x/2)
1-sin(x)/2 = sin^2(x/2)

(That's as far as i've gotten on this one...but i don't know if i'm in the right direction or what to do next?)

2)
sin2x = 1 / tanx + cot2x
2sin(x)cos(x) = ''
sin(x) * cos(x) * sin(x) = ''

(The same from #1 applies to this problem)

Elijah the Wood
Nov7-04, 02:03 PM
can anyone help?