And then the derivative of negative four is just zero, so it's just gonna be times four x. So that's what she needed to do in order for it to be correct. So she had to have this times four x here, times four x. So not correct, she didn't correctly apply the chain rule. So let's do another one of these. So here it says Nejoman tried to find the derivative of sine of seven x squared plus four x. Here is his work.