1. For which following condition, will the cross product of two vectors be zero?(adsbygoogle = window.adsbygoogle || []).push({});

a. If the angle between them is 90°.

b. If the angle between them is 0°.

c. If the angle between them is 45°.

d. If the vectors have the same magnitude.

2. If a = (5, 2) and b = (-3, 1), then which of the following vectors represent 3a - 2b?

a) (9, 4)

b) (9, 8 )

c) (21, 8 )

d) (21, 4)

3. Given the vectors a = (1, 3, 4) and a = (4, 5, -4), which of the following represent a × b?

a) (8, -20, 7)

b) (-32, 20, -7)

c) (4, 15, 16)

d) -3

4. In the previous question, what is the angle between the two given vectors to the nearest degree?

a) 94°

b) 86°

c) 36°

d) 24°

5. If ƒ'(c) < 0 then ƒ(x) is decreasing and the graph of ƒ(x) is concave down when x = c.

True

False

6. If ƒ′(x) > 0 when x < c and ƒ′(x) < 0 when x > c, then ƒ(x) has a maximum value when x = c.

True

False

7. Which of the following would best represent the statement "the plane is flying to the left of me, but is slowing down to come around for another pass?"

a) v(t) > 0 and a(t) > 0

b) v(t) > 0 and a(t) < 0

c) v(t) < 0 and a(t) > 0

d) v(t) < 0 and a(t) < 0

8. A ball is thrown downward from the top of a 20 m tall building with an initial velocity of 15 m/s. What equation could be used to model its height, h(t)?

-4.9t^2-15t+20

9. What is the simplified average rate of change between x = 2 and x = 2 + h for the function:

a. ƒ(x) = x^2?

4+h

b. ƒ(x) = 1/x?

-h/2(2+h)= -1/4

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# Homework Help: Couple multiple choice: Confirmation needed

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