Sunday

February 14, 2016
Posted by **some kid** on Thursday, January 22, 2009 at 8:13pm.

1) x (x+1) dx

2) (x^3-4)/ (x^2) dx

3) (3sinx) dx

4) (5secxtanx) dx

5) (1/x) dx

6) (e^x - 2x) dx

7) (3)/((1-x^2)^1/2) dx

I picked the antiderivatives i did not know how to do. Please show me how to do a couple of these.

- AP Calculus -
**some kid**, Thursday, January 22, 2009 at 8:20pmthe weird symbols in front are supposed be integral signs but watever. i got number 1 and i have the rest i need someone to check the rest.

2)(1/2x^2)/(-4x)

3)-cosx

4)5secx + c

5)0

6)e^x - x^2

7) 3sinx

- AP Calculus -
**Reiny**, Thursday, January 22, 2009 at 10:34pm#2, I would change

(x^3-4)/ (x^2) to x - 4x^-2

and the integral of that is

(1/2)x^2 + 4x^-1 + c

check by differentiating my answer, it is right.

#3, you had

-cosx, how could you get the 3sinx from that?

should have been -3cosx + c

#4

if y = secx

isn't y' = secxtanx ??

take care of the 5, and you are done

#5, you should recognize some standard functions and their derivatives,

if y = lnx

isn't y' = 1/x ??? , so .....

#6, good

#7, how can the derivative of 3sinx, your answer, possibly be (3)/((1-x^2)^1/2) ?????