# Search results

1. ### Trig derivatives

Homework Statement \inte^{2x}sin(3x)dx Homework Equations integration by parts formula The Attempt at a Solution = 9/10e^{2x}(sin(3x)-1/3cos(3x)) I don't think I am taking the derivative of sin(3x) correctly thanks for taking a look :)
2. ### The Origins of the Universe?

So I stumbled upon a video on the internet which made an analogy of mass creating a curve in the blanket of spacetime in which objects of smaller mass rotated about it. Which lead me to belive this is gravity. But aren't there billions upon billions of things within the universe which have mass...
3. ### Prof = Wrong?

Homework Statement lim |x-1|/x^3-1 x-->1+ Homework Equations The Attempt at a Solution This is from a "practise test" and the prof wrote his solution on it... I'm having a hard time figuring out why (x^3-1) = (x-1)(x^2+x+1) which is what he used to find the limit...
4. ### Phantastic Photons

Are photons released from a lightsource at a particular rate? Im pondering this because i got the idea if a laser pointer were attached to a rotating cylinder and rotated at the speed of light (impossible I know) I wonder what the image the laser beam would produce on the wall?