cos(2x)sec^2(x)csc^2(x)
=
cot^2(x)-tan^2(x)
When verifying trig identities, you CANNOT cross onto both sides. Only work on one side at a time & it should always come out equal.
I've tried this multiple times and I can't seem to get it right. Although, I do know that it is possible. Thanks for your time. Please show your steps.
=
cot^2(x)-tan^2(x)
When verifying trig identities, you CANNOT cross onto both sides. Only work on one side at a time & it should always come out equal.
I've tried this multiple times and I can't seem to get it right. Although, I do know that it is possible. Thanks for your time. Please show your steps.
-
cos(2x) sec²x csc²x
= cos(2x) * 1/cos²x * 1/sin²x
= (cos²x − sin²x) / (cos²x sin²x)
= (cos²x − sin²x) * 1 / (cos²x sin²x) ----------> replace 1 with cos²x + sin²x
= (cos²x − sin²x) * (cos²x + sin²x) / (cos²x sin²x)
= (cos⁴x − sin⁴x) / (cos²x sin²x)
= cos⁴x/(cos²x sin²x) − sin⁴x/(cos²x sin²x)
= cos²x/sin²x − sin²x/cos²x
= cot²x − tan²x
= cos(2x) * 1/cos²x * 1/sin²x
= (cos²x − sin²x) / (cos²x sin²x)
= (cos²x − sin²x) * 1 / (cos²x sin²x) ----------> replace 1 with cos²x + sin²x
= (cos²x − sin²x) * (cos²x + sin²x) / (cos²x sin²x)
= (cos⁴x − sin⁴x) / (cos²x sin²x)
= cos⁴x/(cos²x sin²x) − sin⁴x/(cos²x sin²x)
= cos²x/sin²x − sin²x/cos²x
= cot²x − tan²x
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cos(2x) sec²(x)csc²(x)
equals
(cos²x-sin²x )sec²(x)csc²(x)
equals
(cos²x- sin²x )
▬▬▬▬▬
cos²x sin²x
equals
cos²x ...……….. ..sin²x
▬▬▬▬▬..-..▬▬▬▬▬
cos²x sin²x.......cos²x sin²x
equals
.1...……….. 1
▬▬..-..▬▬▬▬▬
sin²x.......cos²x
equals
csc² x - sec²x
Now it turns out that
1 + tan² x = sec²x
and
1 + cot²x = csc² x
so
csc² x - sec²x
equals
1+ cot²x - (1 + tan²x)
equals
1+ cot²x - 1 - tan²x
equals
cot²x - tan²x
equals
(cos²x-sin²x )sec²(x)csc²(x)
equals
(cos²x- sin²x )
▬▬▬▬▬
cos²x sin²x
equals
cos²x ...……….. ..sin²x
▬▬▬▬▬..-..▬▬▬▬▬
cos²x sin²x.......cos²x sin²x
equals
.1...……….. 1
▬▬..-..▬▬▬▬▬
sin²x.......cos²x
equals
csc² x - sec²x
Now it turns out that
1 + tan² x = sec²x
and
1 + cot²x = csc² x
so
csc² x - sec²x
equals
1+ cot²x - (1 + tan²x)
equals
1+ cot²x - 1 - tan²x
equals
cot²x - tan²x
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yes. Rick Astley is a mom.
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mom