For the first question find dy/dx at x equals 0. This will be the gradient of the tangent. You can find the normal using this.
The equation of a parabola is given by (x^2) -4x - 2y + 8 =0*
Find the equation of the normal at (0,4)*
2. A woman walks 120 meters on a bearing of 312 then turns and walks for a further 96 meters on a bearing of 056*
How far is she from her starting point,
And find the bearing of the woman from her starting point.*
Intersect in forth quadrant, find the point of intersection.*
Find x intercepts and hence find the area under the curve*
Two straight roads run from point O. One heads west while the other heads south.*
Person A is 24km west of point O whilst person A is 18km south of O.*
Person A walks at 2km/h towards o, where as person B walks 4km/h away from O.*
Show that after t hours, the area A km^2 of triangle AOB is given by:*
Calculate rate of change in the area after 1 hour
When does this triangles are start to decrease?
the area of the sector of a circle, radius r units, subtending an angle of (theta) at the center is 100(pie)cm^2*
Show that the perimeter of the sector can be given by*
P= 2r + 200/r*
Find the radius of the circle that makes the perimeter of the sector a minimum.*
See rule #4 and rule #8: http://www.mathhelpforum.com/math-he...hp?do=vsarules.