# Thread: Ack - Simple Question (y')

1. ## Ack - Simple Question (y')

I just have a real quick simple question..

I'm doing Implicit Differentiation, and I've had a mind slip.

What's the derivative of 4yx implicitly?

I know poroduct rule = 4y(1) + x(I forgot the derivative of 4y!)

So basically...what's the derivative of 4y?

2. Originally Posted by Super Mallow
I
What's the derivative of 4yx implicitly?
That depends.

If you desire to compute $\displaystyle y',$ then apply the product rule and apply the chain rule for $\displaystyle y.$ Otherwise, if you desire to compute $\displaystyle x'$ then apply the product rule and apply the chain rule for $\displaystyle x.$

3. Originally Posted by Super Mallow
I just have a real quick simple question..

I'm doing Implicit Differentiation, and I've had a mind slip.

What's the derivative of 4yx implicitly?

I know poroduct rule = 4y(1) + x(I forgot the derivative of 4y!)

So basically...what's the derivative of 4y?
Differentiating with respect to x?

d/dx 4yx = 4[y*1(dx/dx) +x*1(dy/dx)] = 4[y(1) +x(dy/dx)] = 4y +4x(dy/dx)

4. Thanks for the help...I ended up getting it