## superduper 4 years ago Can someone explain how to get the derivative of 3x^2 + 15x + 5?

1. misterf

there is a standard technique for taking the derivatives of a polynomial. first find the terms with similar degrees of x and combine them.

2. misterf

(that's already done in this case, heh).

3. superduper

Thanks guys I just started calculus

4. misterf

then decrement the exponent by one, and multiply the former exponent with the coefficient.

5. julie

If you're deriving a single one of those terms, the move is this: $ax^b$ The derivative of this is: $a \cdot b \cdot x^{b - 1}$ The exception is for a constant (no power of x), which derives to 0.

6. misterf

calculus is great! it opens up a whole new realm of math.

7. julie

In this case, you can do that for each one and you get: $3 \cdot 2x + 15 \cdot 1 = 6x + 15$

8. misterf

looks like julie's got this one :)

9. julie

thanks for the medals :)