## Help with IntegralS! Very Important! Quick!

I start do 6th and.. have problems in middle. see in atach
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 so the rsult of 5: $$\intdu=\arcsin \frac{x}{2} + C$$ ?
 Recognitions: Homework Help I have no idea what the "tg" is, but I deduce its the tangent function. Even if it isnt, let $$u=\sqrt{x}$$ Then $$\frac{du}{dx} = \frac{1}{2u}, dx = 2u du$$ so the integral becomes $$\int \tg u \frac{2u}{u} du = 2\int \tg (u) du$$ EDIT: As to post 36, q5, yes that is the answer. The reason you can not write it as you did previously is because it is only valid for n E Z, but we need it to be valid for all real values of n.
 Gibs $$u=\sqrt{x}$$ $$du=\frac{1}{2\sqrt{x}}dx$$ then $$dx=2\sqrt{x}du$$
 Recognitions: Homework Help Check your typing, you forgot to use the right hand brace } instead of right breacket ). Anyway, then you are correct. However, didn't we say $u=\sqrt{x}$?
 Recognitions: Homework Help You know either way it doesn't matter. You are stuck with $$2\int \frac{\sin x}{\cos x} dx$$ which can be solved by letting u = cos x
 right result? Attached Thumbnails
 Recognitions: Homework Help Nope. $$2\int \frac{\sin x}{\cos x} dx$$ let u = cos x, then du = - sin x dx $$-2\int \frac{1}{u} du = -2\log_e u + C = -2 \log_e (\cos x) + C$$

 Quote by Gib Z Nope. $$2\int \frac{\sin x}{\cos x} dx$$ let u = cos x, then du = - sin x dx $$-2\int \frac{1}{u} du = -2\log_e u + C = -2 \log_e (\cos x) + C$$
U right, i agree with u. I made a child mistake =(
simply I sit near computer and do homework already 6 hours and have square head
 start the 7th. Stop in the middle. See in atach. Attached Thumbnails
 Mentor So you have the integral of sec u= 1/cos u. To compute this, try multiplying top and bottom by sec u+tan u.
 i dont understand u cristo =(
 stop dont tell me anything 5 minut i try tio solve it again.
 secu^2= 1+tgu^2 => secu=sqrt(1+tgu^2) so compare 3rd step and last in atach . hmm
 Mentor $$\sec u=\sec u\cdot\left(\frac{\sec u+\tan u}{\sec u+\tan u}\right)$$. Can you integrate this? [Hint: How is the numerator related to the denominator?]
 ou... sorry =) how to delete.... -) its mistake
 to cristo... no i cant =*(

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