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# Differenciation of Exponentials A2 Maths

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1. Hi, Can someone please explain the 3rd line?
2. (Original post by Banana ice-cream)
Hi, Can someone please explain the 3rd line?
What don't you understand? Differentiating with respect to gets you and differentiating with respect to gets you .

So all they've done is differentiated both sides of the second line.
3. (Original post by Zacken)
What don't you understand? Differentiating with respect to gets you and differentiating with respect to gets you .

So all they've done is differentiated both sides of the second line.
When you differenciate x ln a with respect to x, why don't you get 1/a?
4. (Original post by Banana ice-cream)
When you differenciate x ln a with respect to x, why don't you get 1/a?
Because is just a number, and so is . You wouldn't say that if you differentiate you'd get , would you?

So, since is a constant then .
5. (Original post by Zacken)
Because is just a number, and so is . You wouldn't say that if you differentiate you'd get , would you?

So, since is a constant then .
I still don't understand. But then, when you differentiate y=lnx why do you get dy/dx = 1/x?
6. (Original post by Banana ice-cream)
I still don't understand. But then, when you differentiate y=lnx why do you get dy/dx = 1/x?
Because isn't a constant, it is the variable you are differentiating with respect to. If you did then you'd get . But here you are doing .

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