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Help on verifying the identity in TRIG?

Here's the problem:

sin t csc((pi/2))-t) = tan t

I used one of the cofunction identities but I got stuck..can you help explain how to do this?

Update:

Thank you for explaining it. :)

I need to practice doing these problems so I can get better.

1 Answer

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  • Anonymous
    1 decade ago
    Favorite Answer

    to make thing easier, ill write pi/2 as 90 since its 90 degrees

    sin(A-B) = sinAcosB - cosAsinB

    sin90 = 1

    cos90 = 0

    sin(90-t)

    = sin90cos(t) - cos90sin(t)

    = 1 x cos(t) - 0 x sin(t)

    = cos(t)

    (sin t)(csc(90-t))

    = (sin t)(1/sin(90-t)) (since csc = 1 / sin)

    = (sin t)/(sin(90-t))

    = (sin t)/(cos t) (proven earlier)

    = tan t

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