Question

1 + tan^2 (5) - csc^2 (85) = ?

Would this equal 0

could someone explain this to me and the correct answer?

Answer 1

are those degrees ?
I will assume you are familiar with the basic identities.

1 + tan^2 (5°) - csc^2 (85)
= sec^2 (5) - csc^2(85
but sec Ø = csc(90-Ø)
so sec(5) = csc(85)
so continuing from above

= csc^2(85) - csc^2(85)
0

Answer 2

Correct if you work in degrees.
For details, see response:

http://www.jiskha.com/display.cgi?id=1299028595

Answer 3

tan 5=sin5/cos5=cos85/sin85

now, since they are the same angles, I will call that angle T

1+cos^2t/sin^t -1/sin^2t=

(sin^2+cos^2 -1)/sin^2t=

0

check that.

Answer 4

yes, they are degrees, thank you soo much!

Answer 5

geepers, three folks knew how to do it. I bet millions of others have laboured through it also.

Answer 6

And all within one minute of each other !

Answer 7

Good