Question

Find the first derivative of y=17x^-2 + 13x^3 - 2x

Answer 1

The derivative should be -34x^-3 +39x^2 - 2

Answer 2

how do u get negative 3

Answer 3

When you take the derivative, you subtract one from the power. So (-2) - 1 = -3

Answer 4

oh ok. So you multiply the power and the coefficient then subtract one from power to get the answer right?

Answer 5

Yep, that's right :)

Answer 6

oh ok. i never thought it would be easy, but thanks.

Answer 7

You're welcome! And as a note, this is the "shortcut" way

Answer 8

what's the short cut?

Answer 9

The way we found the derivative just now, the regular way is the definition of derivatives

Answer 10

wow really? that's the short cut?

Answer 11

Yup, it's the shortcut. The regular way is just really long and that makes it really confusing to a lot of people

Answer 12

My teacher showed us the long way and it was confusing especially when he get to the division part

Answer 13

Oh yeah, I get you. Even after 2 years of Calculus I still get really super confused. I usually teach the simplified version without the fancy nonsense so it's easier to understand :)

Answer 14

Yeah, the simplied version is much easier and make more sense

Answer 15

As long as your teacher doesn't ask for the definition of derivatives, you can use this method instead

Answer 16

oh yeah true

Answer 17

Hope I helped! :)

Answer 18

You helped a lot and made it more easier