Answer:

Step-by-step explanation:
We have
this equals to
now we try to agrupate to have exponent of 2 that we can cancel
we can take out the ones with exponent from the root

cos x and sin x are sinusoids
X^2 is not
the answer is C.
Answer:
$3.24
Step-by-step explanation:
0.87 x 7 = 6.09
9.33 - 6.09 = 3.24
First term = 12
Solution:
A4 = 24
A12 = 56
An = A1 + (n-1)d; this defines the formula of an arithmetic series
A4 = 24 = A1 + (4-1)d
A4 = 24 = A1 + 3d
A12 = 56 = A1 + (12-1)d
A12 = 56 = A1 + 11d
Subtract A4 from A12 to get d (distance)
(56 = A1 + 11d) - (24 = A1 +3d)
32 = 8d
d = 4
Substitute d = 4 into A4
A4 = 24 = A1 + 3(d)
24 = A1 + 3(4)
24 = A1 + 12
24 - 12 = A1
12 = A1