reviewing some trigonometry, definitely dont remember how to do it and I'm totally drawing blanks. Could anyone tell me how to go about solving the following?

if tanx=−0.5 then tan(−x)

If sinx=0.5 then sin(−x) =

If cosx=0.3 then cos(−x)=

If tanx=−2.5 then tan(pi+x)=

any help would be greatly appreciated
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you're asking UG for advice on what to do with your life? Prepare to have a career as a fluffer in the porn industry...
Math Thread.
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You just single-handedly caused an entire future generation of people to be flushed down the toilet.

Good job, TS.
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Can't you just use a calculator and substitute in the negatives?

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How about just send a ship at the speed up light directly to the sun, and the gravity will pull it towards the sun, thus speeding it over the speed of light.