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3 votes
Simplify the expression.

((cscy+coty)(cscy-coty))/(cscy)

A. -sin(y)
B. cos(y)
C. sin(y)
D. csc(y)

50 points!!!

User StKiller
by
8.3k points

2 Answers

5 votes

Answer:

sin y

Explanation:

Start with the numerator

(csc y + cot y)(csc y - cot y)=csc²y - cot²y

cot²y = csc²y -1

replace cot²y with csc²y -1

csc²y - csc²y +1 =1

Then 1/csc y = sin y

User Slouc
by
8.7k points
5 votes
should be B. I would get someone to double check me though!

User Attila Naghi
by
7.3k points