# Thread: can some help diffreratiated this thank you

1. ## can some help diffreratiated this thank you

can someone help me differentiate this first and second diffrentiation.

https://ibb.co/nhrir7

2. ## Re: can some help diffreratiated this thank you

Typically, when you learn Calculus, almost the first thing you learn is that the derivative of $\displaystyle x^n$ with respect to x is $\displaystyle nx^{n-1}$. Nor long after you should have learned that the derivative of $\displaystyle e^x$ is $\displaystyle e^x$ and the "chain rule". For the first one, the derivative of $\displaystyle aW- bW^2$, with respect to W, is $\displaystyle a(1W^0)+ b(2W^1)= a+ 2bW$. For the second, the derivative of $\displaystyle -exp(-\theta W)$, with respect to W, is $\displaystyle -exp(-\theta W)$ times the derivative of $\displaystyle -\theta W$ which is $\displaystyle -\theta (1W^0)= -\theta$. Putting those together, the derivative of $\displaystyle -exp(-\theta W)$ is $\displaystyle \theta exp(-\theta W)$.