Thursday, August 30

Lesson 2.4

Reminders:
The Chain Rule
y=2(x^2+1)^3

The 3 moves to the front and is subtracted by 1 =D
y prime=6(x^2+1)^(2) *2x

Really the 3 moving to one and subtraction of one is kind of like the power rule (remember that in 2.1?). Remember to keep everything inside the same. And then take the derivative of inside later at the end. You can check the proof on page 131 to see why it works if you so wish.

Using Trig
y=Sin (x^2)
y prime=Cos (x^2) *2x

Homework: 7-29 odd, 39-63 odd, 67, 72, 83, 88, 92



6 comments:

Ms. Jones said...
This comment has been removed by the author.
Ms. Jones said...

I'm looking at this:

Using Trig
y=Sin 3x
y prime=Cos (x^2) *2x

I think it should be y=sin(x^2) because then y'=cos(x^2)*2x

Anonymous said...

On #67 it would be
y=(9/5)(x-3)+5 if you're too lazy to change it to the form the back of the book had.

._.; and if I typed something wrong do tell me.

Hanna said...

Using Trig
y=Sin 3x
y prime=Cos (x^2) *2x

I think it should be y=sin(x^2) because then y'=cos(x^2)*2x
---
^^; oops. I think I was going to type something else but then change it.

How do you get the prime thingie?

Ms. Jones said...

On 67)

y=(3x^2-2)^(1/2), find y' at (3,5) then use the point slope formula.

y'=(1/2)(3x^2-2)^(-1/2)*6x so
y'(3,5)=(1/2)(3*9-2)^(-1/2)*(18) which is 9/5.

So y=(9/5)(x-3)+5 and YEP your answer is correct!!

Ms. Jones said...

For the prime thing I used the lower case quote by the "enter" key.