Calculus/Identities

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Question
i dont know where to start with this problem;
 Prove that the equation is an identity
sinX/(1-cosX) + (1-cosX)/sinX = 2 cscX

please send as soon as possible
THANK YOU

Answer
Hello Kate,

OK, combine the left side by getting a common denominator,
which is sin(x)[1-cos(x)]:
==>[sin(x)^2 + (1-cos(x))^2]/[sin(x)(1-cos(x))]
= [sin(x)^2 + 1 - 2cos(x) + cos(x)^2]/[sin(x)(1-cos(x))]
= [sin(x)^2 + cos(x)^2 + 1 - 2cos(x)]/[sin(x)(1-cos(x))]
= [1 + 1 - 2cos(x)]/[sin(x)(1-cos(x))]
= [2 - 2cos(x)]/[sin(x)(1-cos(x))]
= 2[1-cos(x)]/[sin(x)(1-cos(x))]
= 2/sin(x)
= 2csc(x)

OK?

Abe

Calculus

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Abe Mantell

Expertise

Hello, I am a college professor of mathematics and regularly teach all levels from elementary mathematics through differential equations, and would be happy to assist anyone with such questions!

Experience

Over 15 years teaching at the college level.

Organizations
NCTM, NYSMATYC, AMATYC, MAA, NYSUT, AFT.

Education/Credentials
B.S. in Mathematics from Rensselaer Polytechnic Institute
M.S. (and A.B.D.) in Applied Mathematics from SUNY @ Stony Brook

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