Take the 2-minute tour ×
Mathematics Stack Exchange is a question and answer site for people studying math at any level and professionals in related fields. It's 100% free, no registration required.

... Express you answer as y^-9 =

I assume I need to set up a differential equation, but I do not even know where to begin.

share|improve this question
add comment

1 Answer

Solve the differential equation $$\frac{dy}{dx}=\frac{y^{10}}{x^3}$$ with initial condition $y(1)=1$. The variables can be separated, so solving the DE should not be difficult.

Why? Because the differential equation above says exactly that the slope of the tangent line at $(x,y)$, which is $\dfrac{dy}{dx}$, is equal to the expression on the right.

share|improve this answer
1  
I got (-1/9)y^(-9)=(-1/2)x^(-2)+C –  Ryan Oct 4 '12 at 22:25
    
But it's not right. –  Ryan Oct 4 '12 at 22:26
    
NVM got it. Thanks! –  Ryan Oct 4 '12 at 22:28
    
You need to evaluate $C$ using the initial condition. –  André Nicolas Oct 4 '12 at 22:29
add comment

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.