#### Differentiation question

Timothy Lee

1

I have two functions here:
H(p) = 0,03p^(10) + 1,2p^(6) - p
This would then be H'(p) = 0,3p^(9) + 7,2p^(5) - 1
And I think I understand this because -p is -1p
But in this function:
K(x) = 5x^(7) + ax^(2) + b
The answer is K'(x) = 35x^(6) + 2ax
I don't understand where the b is now and why a is in there, I think it may be because a is multiplying, but why does nothing happen with b? Wouldn't b be 1 then? Or does it need to be a letter which is in K(..) to count? (so x). And I also thought a would be 1 actually.