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Prove one trig identity please?
steps please
(csc(-x) +1) / cos(-x) + cot (-x) = sec x

2007-02-22 14:06:26 · 2 answers · asked by k 1 in Science & Mathematics Mathematics

2 answers

The right identity is : (csc(-x) +1) / (cos(-x) + cot (-x)) = sec x
Rem. : csc(-x) = - csc(x), cos(-x)=cos(x), cot(-x)= - cot(x),
csc(x) = 1/sin(x), cot(x)= cos(x)/sin(x)
L. H. S. = (- csc(x) + 1)/(cos(x) - cos(x)/sin(x))
.............= (- 1/sin(x) + 1)/(cos(x) - cos(x)/sin(x))
.............= (- 1 + sin(x))/(cos(x) sin(x) - cos(x))
.............= ( -1 + sin(x)) / [cos(x) ( sin(x) -1)]
............ = 1/ cos(x) = sec(x) = R.H.S. (q. e. d.)

2007-02-22 20:38:35 · answer #1 · answered by a_ebnlhaitham 6 · 0 0

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2016-12-04 19:58:48 · answer #2 · answered by papen 4 · 0 0

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