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# Exponentials and Logs. watch

1. im probably not approaching the question properly, need a bit of support, please.
Question: The curve C has the equation and passes through the point P with x-coordinate 1.

a) Find an equation for the tangent to C at P.

The tangent to C at P meets the coordinate axes at the points Q and R.

b) Show that the area of triangle OQR, where O is the origin, is

so, i've figured out that:

subbing, x=1 into y

sub x = 1

here, I'm unsure if dy/dx can equal m or the gradient...???

i really dunno if this correct or not.
2. When you sub x = 1 into dy/dx the value you get will be the gradient, m, of the tangent. Therefore your tangent equation will be y = 2(e-3)x + c. I'm guessing you know how to find c.
3. thats fine up till where you randomly divide by 2 in the 2nd to last line of working....
4. part b) just subbing y=0 and x=0 into the eqn of the line will find the two coordinates. and then should be some simple area of triagnle = 1/2 x b x h...
5. (Original post by Dagrath)
When you sub x = 1 into dy/dx the value you get will be the gradient, m, of the tangent. Therefore your tangent equation will be y = 2(e-3)x + c. I'm guessing you know how to find c.
c=y-intercept so, x=0
sub x=0 into the equation?
6. (Original post by GHOSH-5)
part b) just subbing y=0 and x=0 into the eqn of the line will find the two coordinates. and then should be some simple area of triagnle = 1/2 x b x h...
thank you!

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