1. The explicit rule for the geometric sequence is an = 7(−4)(n − 1)
What is the recursive rule for the sequence?
A. an = −7(an+1 ), a1 = 4
B. an = −4(an−1 ), a1 = 7
C. an = −4(an + 1 ), a1 = 7
D. an = −7(an−1), a1 = 4
2. Determine the quadrant the terminal side of an angle with measure of 7π/6?
A. Quadrant 1
B. Quadrant 2
C. Quadrant 3
D. Quadrant 4
3. Jacob is standing 112 m from a building. The angle of elevation from where he is standing on the ground to the top of the building is 62 degrees. How tall is the building? Round to the nearest whole number.
4. What is the value of cos C?
A. 8/17
B. 17/8
C. 17/15
D. 15/8
1. B is the correct answer.....the first term, a1, is 7
And an = -4*a n-1
2. 7pi / 6 converted to degrees is
7pi / 6 * 180 / pi =
[ 7pi ] / [ 6 pi ] * 180 =
(7/6) * 180 =
7 ( 180 / 6 ) =
7 * 30 =
210°.....and this is a 3rd quadrant angle
3. We can use the tangent here
tan 62 = x / 112 multiply both sides by 112
112 * tan 62 = x ≈ 210.6 ft = 211 ft
4. None of the answers are correct
cos C = adjacent side / hypotenuse = 15 / 17