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# Help !!differentiation question watch

1. Points P1 (1, y1), P2 (1.01, y2) and P3 (1.1, y3) lie on the curve y = kx2
. The gradient of the chord
P1P3 is 6.3 and the gradient of the chord P1
P2 is 6.03.
(iii) What do these results suggest about the gradient of the tangent to the curve y = kx2 at P1?

(iv) Deduce the value of k.

Could someone show me how to work these out ?thank you
Points P1 (1, y1), P2 (1.01, y2) and P3 (1.1, y3) lie on the curve y = kx2
. The gradient of the chord
P1P3 is 6.3 and the gradient of the chord P1
P2 is 6.03.
(iii) What do these results suggest about the gradient of the tangent to the curve y = kx2 at P1?

(iv) Deduce the value of k.

Could someone show me how to work these out ?thank you

From this definition, what value can you suggest that the chord line's gradient is getting closer to as it tends to the tangent line at P1?
Points P1 (1, y1), P2 (1.01, y2) and P3 (1.1, y3) lie on the curve y = kx2
. The gradient of the chord
P1P3 is 6.3 and the gradient of the chord P1
P2 is 6.03.
(iii) What do these results suggest about the gradient of the tangent to the curve y = kx2 at P1?

(iv) Deduce the value of k.

Could someone show me how to work these out ?thank you
Think about it. Notice the x-coordinates, they are all VERY close to each other so since the gradient of P1P3 is 6.3, and the gradient P1P2 is 6.03, what would the gradient be at P1?

Using the answer above, you can deduce the value there using differentiation.
4. (Original post by NotNotBatman)

From this definition, what value can you suggest that the chord line's gradient is getting closer to as it tends to the tangent line at P1?
getting closer to 6
getting closer to 6
getting closer to 6
Yes, now you can do part (b) using that answer.
7. (Original post by RDKGames)
Think about it. Notice the x-coordinates, they are all VERY close to each other so since the gradient of P1P3 is 6.3, and the gradient P1P2 is 6.03, what would the gradient be at P1?

Using the answer above, you can deduce the value there using differentiation.
thank you
8. (Original post by NotNotBatman)
Yes, now you can do part (b) using that answer.
thank you soo much

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