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# C3 differentiating exponential functions watch

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1. Hiya, I'm really stuck on this maths question and would really appreciate it if you guys could help me to solve it.

The question is e^-2x /(x+1)^1/2.

I have decided to use the quotient rule for this and have substituted the u and v values and the differentiated u and v values into the quotient rule formula but I don't know what to do from there. The answer is -(4x+5)e^-2x / 2(x+1)^ 3/2

Please could you help me, thank you
2. Sorry this might be a bit late, since you posted this 4 hours ago, but I'll post anyway in case you're still having trouble with it.

After you've substituted the values into the formula, you should end up with -e^(-2x) 2(x+1)^(1/2) - e^(-2x) (1/2)(x+1)^(-1/2) in the numerator of the fraction. Since the power of the second part of the numerator is negative, convert that into a fraction and then find the common denominator (all in the fraction in the numerator of the overall fraction). Try factorising e^(-2x) from there, and you should be able to get the answer quickly
3. (Original post by DawnAR)
Sorry this might be a bit late, since you posted this 4 hours ago, but I'll post anyway in case you're still having trouble with it.

After you've substituted the values into the formula, you should end up with -e^(-2x) 2(x+1)^(1/2) - e^(-2x) (1/2)(x+1)^(-1/2) in the numerator of the fraction. Since the power of the second part of the numerator is negative, convert that into a fraction and then find the common denominator (all in the fraction in the numerator of the overall fraction). Try factorising e^(-2x) from there, and you should be able to get the answer quickly
Heya, thank you for your help
4. You're welcome! Glad it helped

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