Either I read it wrong, or the examiners will need to change the marks. The only thing I can think of is that maybe they meant take the bearing from C, not A/B. But I am pretty sure this is what it said.
So basically, this one question messed me up in my maths exam today. Everything we went over yesterday concerning tangent lines/derivetives I went pretty well in.
The question was. There are two lookout points. A and B. There is a campirefire at a bearing of 40 degrees from A. From point B, the...
As we were talking about earlier.
f(x) = x^2 + 3x + 6
f ' (x) = 2x + 3
P1 = (0, f(0))
f ' (0) = 3.
This is not symetrical...
I hope you guys enjoy my question bombarding. As there are a lot of maths concepts that make me want to cry. It's funny, half the people in my degree fail their...
lets say we plot the point a on (0, f(0)) (the function being f(x) = x^2 + 3x + 6)
now the derivative of f(x) = x^2 + 3x + 6 is apparently f ' (x) = 2x + 3
f ' (a) = 2*a + 3
f ' (a) = 2*0 + 3
f ' (a) = 3
Is there a different method of getting the derivative with functions like x^2 and f(x)...
1 question. If you end up with 2x + h + 3.
Then limit -> 0 to get 2x + 3...
f ' (0) = 2*0 + 3
f ' (0) = 3.
Shouldn't the tangent line to x = 0 have a gradient of 0 not 3?
Saved my life with that. It's not that I don't know the order. It's that I forget things like what you just did with factoring out h. I always forget these things and it makes me get them wrong -.-
What h are you supposed to get rid of at this point?
We need to get rid of h because you can't divide by 0. It's just unclear which one of the numerator h's should be divided out...
Or are you supposed to divide every part by h. So you get 2x + h + 3?
is h^2 / h = h?
EDIT: I get it now. Just...
So I started with this function: f(x) = x^2 + 3x + 6
I then got this from it:
m = ((((x + h)^2) + (3*(x + h)) + 6) - (x^2 + 3x + 6)) / ((x + h) - x)
Which I eventually simplified to 2x + h^2 + 3h
And then: limit h -> 0: 2x + h^2 + 3h = 2x
So f ' (x) = 2x
Is that right? By doing this, I...
Re: Help with limits/tangaent line
I have a question. This one always gets me.
Say we have \(\dfrac{9x^2 + 5}{3x^2}\), does that make it \(\dfrac{6x^2 + 5}{1}\)
Also if we have \(\dfrac{6x^2 + 5}{18x^2}\), what would be the simplified answer? This got me in my last test.
EDIT: uhh how do you...
Re: Help with limits/tangaent line
Howcome you cancel the h outside the brackets instead of the other h? Is that because the other h is inside brackets and therefore attached to the 2a?