if u=tan x then du=?

Question

anonymous · Answer

the derivative of tanx.  A piece of advice (take it or leave it): if you rewrite tanx as sinx/cosx then use the quotient rule (and a bit of the product rule) to grind this out, you will probably remember the answer for a lot longer.  That being said, the answer is probably in the back of your book, so here it is: du =  sec^2x dx

precal · Answer

Ajk is correct
you are being asked for the derivative of tanx
best to learn the basic trig derivatives, commit them to memory

dean.shyy · Answer

Tax (x) = Sin (x) divided by Cos (x). The derivative answer for Tan (x) will give you Sec (x) ^ 2.

precal · Answer

yes but I believe you meant tan(x), I have not heard of the new "trig" function called tax (x).  Your route would require the quotient rule.  too much work, just memorize the derivatives........

anonymous · Answer

I wish I could memorize this stuff (without grinding it out an embarrassingly high number of times).

precal · Answer

http://www.dummies.com/how-to/content/how-to-differentiate-the-trigonometric-functions.html seems like someone has a strategy.......