Just Plane Math
Vector Vibes
Conic-tions
Parametrickery
Surface Tension
450

Find the equation of the plane perpendicular to the line

L(t)=<2-4t,2+3t,t-1> 

containing the point (7,8,-9)

-4(x-7) + 3(y-8) + (z+9) = 0
450

Find the angle between

v=<1,-4,-8> and w=<2,6,-3>

you can give your answer as an inverse trig function.

arccos(2/63)

450

See Card (C) - Hyperbolic Paraboloid

C, lambda, e, 4

450

Find the arc length of the curve

s(t) = <et^2, sin(et^2), cos(et^2) >

over the interval [0,  sqrt( ln(7) ) ]

6 sqrt(2)

450

Find the 4th order mixed partial fxyxy for the function

f(x,y) = x2 sin(y) - y2 cos(x)

fxyxy(x,y) = -2 sin(y) + 2 cos(x)

500

Find the equation of the plane through

(1,-1,0), (3,0,0), and (3,1,4) 

N=(2,-4,1), e.g.

2(x-1) - 4(y+1) + z = 0


500

Find the area of the triangle containing the points 

(0,0,0), (1,-3,-1), (2,0,1)

7/2

500

See Card (2) - z2=x2-y2

2 l G iota

500

Find the curvature of the curve

s(t) = <et, et, 1 > 

zero: it is a line

500

Let f(x,y) = y2-x2

x=r sin(t)

y=r cos(t)

Compute (df/dr) at (x,y) = (2,0)

-4

550

Find the equation of the plane containing the line

L= <3+t,1,-5>

which is parallel to the line

L=<1,-3+t,6>

z+5=0 or z=-5

550
Find the distance between the point (-9,2,-12) and the plane

4x-y+8z = 28

18

550

See Card (i) - Level set

H i 3 beta

550

Find the unit normal vector to the curve

s(t) =< (1/2)t2, (1/2)cos(t2), (1/2)sin(t2) > 

N=<0, - sin(t2), -cos(t2) >

550

DAILY DOUBLE

Compute the limit as (x,y) goes to (0,0) of

[(esqrt(x^2+y^2)-1)(sin(1 / sqrt(x2+y2)))]

                                                         

           sqrt(x2+y2)

600

Find the tangent hyperplane to the surface in R4 of the function

w=f(x,y,z) = x2+y2-z2

at the point (1,-2,3,-4)

w=-4+2(x-1) + -4(y+2) + 8(z+4)

600

Find the volume of the 4-dimensional tetrahedron with vertices

(0,0,0,0), (1,0,0,0), (0,-2,0,0), (0,0,3,0), (0,0,0,-4)

Recall that there are 4!=24 such tetrahedra in a 4-dimensional parallelopiped.

1

600

DAILY DOUBLE

Find the surface of intersection in 5-dimensional space of the cone

x2+y2+v2+w2=z2  (z >= 0)

and the hyperboloid

-x2-y2+2z2-v2-w2=1

600

Find the curvature of the curve of intersection of the cylinder

x2+z2=25

and the hyperboloid

x2-y2+z2 = 16

1/5

600

Tiny pyramids are to be manufactured with a square base of side length s=6 cm and height h=8 cm. The error in the side length is up to 0.15 cm and the error in the height is up to 0.25 cm. What is the approximate error in volume? Use the formula

V=(1/3)s2h

dV is about 7.8 cm3

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