Question

find the derivative of 7x3^x.

i got 21^x+ln(3)3^x*7x

Answer 1

Not quite right on the product rule application. Take the derivative of 7x, multiply that by 3^x. Then add to that the derivative of 3^x times 7x.

Answer 2

thats what i did i thought

Answer 3

7(3^x) doesn't equal 21^x

Answer 4

Check the derivative of 7x.

Answer 5

then what does it equal

Answer 6

I can't be reduced from 7(3^x)
Plug a few numbers in for x to see that it can't be reduced.

Answer 7

The derivative of 7x is 7 via the power rule.

Answer 8

As KeapLurnin said, you can't just multiply 7 and 3^x.

Answer 9

Yes. He knows the derivative is 7. It's just multiply it by 3^x that's the problem.

Answer 10

so what would it be then just 7(3^x)

Answer 11

Bingo!

Answer 12

is that the only issue with the problem

Answer 13

Yup....you got the second part right.