412
312
712
514
Correct answer is C
∫2−1(2x2+x)dx
= [2x2+13+x1+12]2−1
= [2x33+x22]2−1
= (2(2)33+222)−(2(−1)33+(−1)22)
= (163+2)−(−23+12)
= 223−(−16)
= 223+16
= 152
= 712
The nth term of a sequence is given by 22n−1. Find the sum of the first four terms.
74
32
42
170
Correct answer is D
Tn=22n−1
T1=22(1)−1
= 2
T2=22(2)−1
= 8
T3=22(3)−1
= 32
T4=22(4)−1
= 128
T1+T2+T3+T4=2+8+32+128
= 170
Solve the inequality: -7 ≤ 9 - 8x < 16 - x
-1 ≤ x ≤ 2
-1 ≤ x < 2
-1 < x < 2
-1 < x ≤ 2
Correct answer is D
-7 ≤ 9 - 8x < 16 - x
-7 ≤ 9 - 8x and 9 - 8x < 16 - x
-7 - 9 ≤ -8x and -8x + x < 16 - 9
-16 ≤ -8x and -7x < 7
∴ x ≤ 2 and -1 < x
-1 < x ≤ 2.
x≤112
x≤212
x≥212
x≥112
Correct answer is B
4x−63≤3+2x2
2(4x - 6) ≤ 3(3 + 2x)
8x - 12 ≤ 9 + 6x
8x - 6x ≤ 9 + 12
2x ≤ 21
x≤212
If f(x)=3x3+4x2+x−8, what is the value of f(-2)?
-24
30
-18
-50
Correct answer is C
f(x)=3x3+4x2+x−8
f(−2)=3(−2)3+4(−2)2+(−2)−8
= −24+16−2−8
= -18