Posted by **Anonymous** on Tuesday, January 3, 2012 at 3:08pm.

The coordinates of the point where the normal to the curve y= 1/3 x^3 + 1/2 x^2 + x at x=1 intersects the y-axis are what?

- Calc -
**Reiny**, Tuesday, January 3, 2012 at 3:21pm
dy/dx = x^2 + x + 1

at x=1 ,slope of tangent is 1+1+1 = 3

so slope of normal is -1/3

when x=1, y = 1/3 + 1/2 + 1 = 11/6

so equation of normal:

y = (-1/3)x + b, at (1, 11/6)

11/6 = -1/3 + b

b = 3/2

y = (-1/3)x + 13/6

for y-intercept, let x = 0

y = 13/6

it cuts at (0,13/6)

check my arithmetic

## Answer This Question

## Related Questions

- Calc - Find the coordinates of the point on the curve xy=6 in quadrant I where ...
- Math - 1. The curve y=10/2x+1 -2 intersects the x-axis at A. The tangent to the ...
- math - A curve has implicit equation x^2-2xy+4y^2=12 a)find the expression for ...
- Calculus - The line that is normal to the curve x^2=2xy-3y^2=0 at(1,1) ...
- Calculus - A curve is defined by the parametric equations: x = t2 – t and y = t3...
- maths - A line intersects the y axis and x axis at the point P and Q ...
- Calculas-Differentiation - Find the equation of the tangent to the curve y=1/2x^...
- math - the tangent yo the curve y=x^2 +5x -2 @ the point (1,4)intersect the ...
- Business Statistics - In each case, sketch the two speciﬁed normal curves...
- math - The line segment joining P(-6,7) and Q(5,-2) intersects the y-axis at ...

More Related Questions