This seems simple but it doesnt really sink in for me.

http://img205.imageshack.us/img205/8137/1241413ii3.jpg

Can i have working out plz. thanx for any help

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- October 25th 2007, 05:02 AMKavXfind gradient, equation, value, graph included.
This seems simple but it doesnt really sink in for me.

http://img205.imageshack.us/img205/8137/1241413ii3.jpg

Can i have working out plz. thanx for any help - October 25th 2007, 09:57 AMhoranSolution
I'm not sure about (i), but you don't need it to find the other two answers.

ii. The slope of the tangent at a is given by dy/dx at a. So , or, at a, . We also know that the value of y(a) is a^2. Using point-slope form, the equation of the tangent is given by:

or

iii. Plugging in the point (2,0) into the equation from (ii), we get

Then:

Since a > 2 by the graph, a must be equal to 4.