FACT: d/dx((1-x)/1+x))= (-2)/((1+x)^2).
Then the integral of (-2/((1+x)^2)))dx = ((1-x)/(1+x)) + c

EVALUATE : the integral of ((-2/((1+x)^2)) dx by letting u=1+x and du=dx
Do you get the same answer as above? EXPLAIN.

Question

FACT: d/dx((1-x)/1+x))= (-2)/((1+x)^2).
Then the integral of (-2/((1+x)^2)))dx = ((1-x)/(1+x)) + c 

EVALUATE : the integral of ((-2/((1+x)^2)) dx by letting u=1+x and du=dx
Do you get the same answer as above?  EXPLAIN.

jhannybean · Answer

Ok, so the first one basically uses the fundamental theorem of calculus, and states if you take the derivative of the function, then the integral of the derivative give you the original function.

anonymous · Answer

$$\int\limits_{}^{} -2 du / u^2$$

dan815 · Answer

yes

dan815 · Answer

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