Originally Posted by

**skeske1234** I just have a quick question:

Example:

(2sinxcosx/sinx) - (cos2x/cosx)

So this is one side of a trig identity. I was just wondering...

in (2sinxcosx/sinx) can you cancel out the sinx and leave it to be (2cosx)

but for the (cos2x/cosx), you cannot cancel out the cos2x and cosx, right?

Or can you NOT cancel out the (2sinxcosx/sinx) and put it as (2cosx) because of the subtraction sign? I don't understand when you can and cannot cancel. Ok for multiplication and division you can cancel, but for addition and subtraction you can only cancel the ones on top of eachother, not across right? or is that wrong?

Main idea:

When can you cancel and when can you not? Provide examples in relation to this please and thank you!