Recent content by jpd5184

what do you mean it can be integrated. why not. its a question i was asked in class so i would think it can be solved.

so its the integral of the square root of 1+ (3cos(x+x^2)(2x+1))^2 integral of cos(x) is sin(x) would i use u substitution. then it would be 1+ u^3/3

dy/dx = 3cos(x+x^2)(2x+1) im not so sure how to to the integral though.

yes around the y-axis. i need help integrating dy/dx do i use u substitution or can i just integrate right away

sorry about that: 0 < x < pi/2 both are greater than or equal to and less than or equal to.

Homework Statement find the length of y=3sin(x+x^2) find its length and area Homework Equations length: integral of square root of 1+ (dy/dx)2 dx area: integral 2pix square root of 1 + (dy/dx)^2 dx The Attempt at a Solution dy/dx = 3cos(x+x^2)(2x)

Homework Statement integral of x^2ln(x)dx Homework Equations The Attempt at a Solution u=ln(x) du= 1/x dv=x2dx x^3/3 integral x^2ln(x)dx = ln(x)x^3/3-intergral(x^3/3)(1/x)

thanks very much, i did learn this technique, just forgot it.

would i just make tanx into sinx/cosx

Homework Statement lim x-o+ (tan(4x))^x Homework Equations The Attempt at a Solution to get the derivative i have to use the chain rule so it would be. lim x- 0+ (x(tan(4x)^x-1)(sec^2(4)

pi/12 isn't giving me the right answer

so it would be pi/3 - pi/4 this would be 4pi/12 - 3pi/12 which would be pi/12 for the answer since its a integral would it be pi/12 + c

That way, the integral is \int_{\pi/4}^{\p/3} \frac{cos(\theta)d\theta}{cos(\theta)}= \int d\theta which is very easy! so does that mean the integral of (pi/3)-(pi/4) just the upper limit minus the lower limit

that is correct, so what i have to do is use trig substitution. ill give it a try. lets see: u= arcsin du= 1/(sqrt(1-t^2)) dt i could then take the 2 outside the integral sign and get 2(integral of arcsin)

lets see: from the original equation: u= t^3 du= 3t^2 (1/3)du=t^2 ok so i messed up. i accidently substituted u in for t^2 but u=t^3. first i have to make sure my substitution values above are right and if using substitution is the right method for solving the problem. is it?