Math homework help

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So I need some help with my math homework. I need to find the slope of the line tangent to the given point y=2x^2 at (-2,8) I know your supposed to find the derivative but I don't know what to so from there
 
So using the power rule you find the derivative (which is its own function that describes the slope of the first function at any giver point. The derivative is 4x. Then you put The x value you want to find the slope of in for the derivative, and you get f'(-2)=-8.
 
Critical point of a function is a maximum or minimum point or its graph, at this point the slope has to be zero. So you find the x value were the derivative = 0. f(x)= 2x^2, f'(x)=4x. so the critical point is at x = 0. Which makes sense because your function is just a parabola.
 
it's a tangent line of an exponential equation/function... not a linear line, totally different bud.

But yeah, that guy a couple posts down is right. But if they're making you do the

f(x-a) - f(a)

--------------

f(a)

or whatever that equation is, then that's totally different. Let me know if thats what you're supposed to do and I can help. Just can't remember the exact equation
 
I dont think he'll be using that method to find the answer... i learned that in precal but skipped it in calc (which im assuming hes taking now)
 
Bump so I dont have to make a new thread,

this projects due tomorrow and ive done math all day and im exhausted and cant get my mind to compute anymore can someone help me with this.

Write an equation (y = mx+b) for the graph of a linear function that:

has slope 5 and y-intercept -5

has slope -5/6 and y-intercept -6/5

has slope -5 and y-intercept 6
 
13575010:DaffyDaDak said:
Bump so I dont have to make a new thread,

this projects due tomorrow and ive done math all day and im exhausted and cant get my mind to compute anymore can someone help me with this.

Write an equation (y = mx+b) for the graph of a linear function that:

has slope 5 and y-intercept -5

has slope -5/6 and y-intercept -6/5

has slope -5 and y-intercept 6

m is the slope and b is the y intercept

oh to be in grade 9 again...
 
13575010:DaffyDaDak said:
Bump so I dont have to make a new thread,

this projects due tomorrow and ive done math all day and im exhausted and cant get my mind to compute anymore can someone help me with this.

Write an equation (y = mx+b) for the graph of a linear function that:

has slope 5 and y-intercept -5

has slope -5/6 and y-intercept -6/5

has slope -5 and y-intercept 6

13575018:erikK said:
m is the slope and b is the y intercept

oh to be in grade 9 again...

A.k.a...

y=5x-5

y=-5/6x-6/5

y=-5x+6
 
13575166:DaffyDaDak said:
pretty sure its 2

It's not. Since f(x) means you put whatever number you have as "x" in the equation, -2 is taking the place of x in the equation. You take -3(-2) + 8 which gives you an answer of 14.
 
Step 1. Use power rule to find derivative of the function 2x^2:

Constant 2 times n (in x^n) times x^(n-1), or x^1, or x

fprime= 4x

Step 2. Plug in x value -2 to find the derivative at that point.

fprime(-2)=4(-2)

fprime(-2)= -8

Step 3. Pee in her butt

Step 4. Slope of the tangent line at (-2, 8)= fprime(-2)= -8

Step 5. Find tangent line using point slope form

y= -8(x+2)+8
 
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