Question

Choose c so that the line y = x is tangent to the parabola
y = x2 + C. They have the same slope where they touch.

Answer 1

@Mohsin007 Any idea where to start?

Answer 2

by derivatives i think

Answer 3

Yes, from the key word "Tangent" :)
Will you show your derivative here ?

Answer 4

dy/dx=2x

Answer 5

Now what's the relation between y' and the tangent line y = x?

Answer 6

equal?

Answer 7

Yep, but equal with ....?

Answer 8

2x=1
x=1/2?

Answer 9

ok ok i got it..:)
at point of tangency
x=x^2+c
1/2=1/4+c
c=1/4

Answer 10

1=2x

Answer 11

why x=0?