Math Core

Unit 1 · Test

Unit 1 test: Vectors and 3D Space

15 questions. Answer them all, then submit to see your score. Solutions unlock after you submit.

This test covers three-dimensional coordinates and spheres, vector operations, the dot and cross products, lines and planes, and cylinders and quadric surfaces.

Question 1

Find the distance between (2,−1,3)(2, -1, 3) and (−4,1,6)(-4, 1, 6).

Enter a number. Fractions like 3/4 and sqrt(2) are OK.

Question 2

Find the radius of the sphere x2+y2+z2−6x+4z=12x^2 + y^2 + z^2 - 6x + 4z = 12.

Enter a number. Fractions like 3/4 and sqrt(2) are OK.

Question 3

Find the unit vector in the direction of ⟨−2,6,3⟩\langle -2, 6, 3 \rangle.

Enter a point like (2, -3)

Question 4

Let a=⟨1,−3,4⟩\mathbf{a} = \langle 1, -3, 4 \rangle and b=⟨5,2,−1⟩\mathbf{b} = \langle 5, 2, -1 \rangle. Find 2a−b2\mathbf{a} - \mathbf{b}.

Enter a point like (2, -3)

Question 5

Find the angle between ⟨1,−1,2⟩\langle 1, -1, 2 \rangle and ⟨2,1,−1⟩\langle 2, 1, -1 \rangle, in degrees, rounded to the nearest tenth.

Enter a number. Fractions like 3/4 and sqrt(2) are OK.

Question 6

Find the value of cc for which ⟨2,c,−1⟩\langle 2, c, -1 \rangle and ⟨c,3,8⟩\langle c, 3, 8 \rangle are orthogonal.

Enter a number. Fractions like 3/4 and sqrt(2) are OK.

Question 7

Find the vector projection of b=⟨6,−3,3⟩\mathbf{b} = \langle 6, -3, 3 \rangle onto a=⟨2,1,−2⟩\mathbf{a} = \langle 2, 1, -2 \rangle.

Enter a point like (2, -3)

Question 8

Compute ⟨2,0,−1⟩×⟨1,3,2⟩\langle 2, 0, -1 \rangle \times \langle 1, 3, 2 \rangle.

Enter a point like (2, -3)

Question 9

Find the area of the triangle with vertices P(1,0,0)P(1, 0, 0), Q(0,2,0)Q(0, 2, 0) and R(0,0,3)R(0, 0, 3).

Enter a number. Fractions like 3/4 and sqrt(2) are OK.

Question 10

Find the volume of the parallelepiped with edges ⟨1,0,2⟩\langle 1, 0, 2 \rangle, ⟨0,3,1⟩\langle 0, 3, 1 \rangle and ⟨2,1,0⟩\langle 2, 1, 0 \rangle.

Enter a number. Fractions like 3/4 and sqrt(2) are OK.

Question 11

The plane through (1,−1,2)(1, -1, 2) perpendicular to the line x=3t, y=1−t, z=2+2tx = 3t,\ y = 1 - t,\ z = 2 + 2t has equation 3x−y+2z=d3x - y + 2z = d. Find dd.

Enter a number. Fractions like 3/4 and sqrt(2) are OK.

Question 12

Find the point where the line x=2−t, y=1+3t, z=4tx = 2 - t,\ y = 1 + 3t,\ z = 4t meets the plane 2x+y−z=72x + y - z = 7.

Enter a point like (2, -3)

Question 13

Classify the lines L1L_1: x=1+t, y=1+2t, z=3−tx = 1 + t,\ y = 1 + 2t,\ z = 3 - t and L2L_2: x=3+s, y=4+s, z=3+sx = 3 + s,\ y = 4 + s,\ z = 3 + s.

Question 14

Find the distance from the origin to the plane 2x−3y+6z=142x - 3y + 6z = 14.

Enter a number. Fractions like 3/4 and sqrt(2) are OK.

Question 15

Identify the surface x2+y2−9z2=9x^2 + y^2 - 9z^2 = 9.