Question

the derivate of h(x)=4/7x is 4/7?

Answer 1

yup

Answer 2

ok i got it now

Answer 3

jimmy can you help me with this
find the slope of the tangent line of f(x)= 2x^2-x+3

Answer 4

best written as (6/7) x though jinnie - so its not confused with 4 divided by 7x

Answer 5

6/7?

Answer 6

yea ok
find derivative of f(x)

f'(x) = 4x - 1
- thats it

Answer 7

so for example the slope of tangent at x = 1 = 4(1) - 1 = 3

Answer 8

sorry i meant (4/7)

Answer 9

so i must find the derivative first which is 2x-1+0

Answer 10

of 2x^2-x+3

Answer 11

yeah - but its 4x - 1
The derivative at a point on a curve is slope of the tangent at that point

Answer 12

oh yea you have to multiply ok i got it

Answer 13

so what is the equation of the tangent line at x=1? is it the same as the slope of the tangent line at the point x=1?

Answer 14

no use the formula
y-y1 = m(x-x1)
to get the equation
at x=1 , y = 2(1)^2 - 1 + 3 = 4

so we need the equation at the point (1,4) with a slope of 3

y - 4 = 3 (x - 1) is equation of the tangent

Answer 15

can i continue with that or is that where it stops

Answer 16

you can simplify that
y - 4 = 3x - 3
y = 3x + 1

Answer 17

so the way to find the equation of the tangent at a point on a curve is to

1. differentiate the equation of the curve to find slope of the curve

2 substitute for slope, and x and y values of the point into the general form
y-y1 = m(x-x1)

Answer 18

alright thanks

Answer 19

how did you get the slope of 3 btw

Answer 20

yw - hope this helps

Answer 21

i found the slope in terms of x by differentiating f(x) = 2x^2 - x +3
f'(x) = 4x - 1 - this the slope in terms of x , at point x=x
so at x = 1, slope is found by plugging x=1 into 4x-1:
slope = 4(1) - 1 = 3

Answer 22

ok thanks