A deli sells 640 sandwiches per day at a price $8 each. A market survey shows that for every $0.10 reduction in the price 40 more sandwiches will be sold. How much should the deli charge in order to maximize revenue? I got the price should be $4.80. Is this right? If not how do you solve this

That is the correct price.

Also, they should sell 672 sandwiches at $4.80 each to maximize revenue.

R=(640+40x)(8-.1x)

Upon differentiating, setting to 0 and solving for x, we get x=32

hi please I want to now what is the integration of this :
sin^4dx

hi please i want to now what is the integration of this :
sin^4dx

Please start your own thread. Folks are more likely to see it that way.

Anyway: \int sin^{4}(x)dx=\int (sin^{2}(x))^{2}dx

=\int\left[\frac{1}{2}(1-cos(2x))\right]^{2}dx

=\frac{1}{4}\int (1-2cos(2x)+cos^{2}(2x))dx

But cos^{2}(2x)=\frac{1}{2}+\frac{1}{2}cos(4x)

So, we ultimately get:

\int sin^{4}(x)dx=\frac{1}{4}\int\left(\frac{3}{2}-2cos(2x)+\frac{1}{2}cos(4x)\right)dx

Now, finish up? It's easier to integrate now. No more powers.

heyy, can you please help me with this? Write 24sin3xcos3x + (10cos^2)3x - 5 in terms of just one sin function.
there's another question on here with the same numbers but the brackets are in a different position and it affects the question. Thank you!

I'll post the link here again, in case you check this thread first.

https://www.askmehelpdesk.com/mathematics/write-24-sin3x-cos3x-10-cos-2-3x-5-terms-one-sin-function-466428.html

I already left a message in your other thread.