The pattern is the amount you need to add increases by 2 each time. Ex. 1+1=2 2+3=5 3+5=8
If y = cos(kt), then its first two derivatives are
y' = -k sin(kt)
y'' = -k² cos(kt)
Substituting y and y'' into 49y'' = -16y gives
-49k² cos(kt) = -15 cos(kt)
⇒ 49k² = 15
⇒ k² = 15/49
⇒ k = ±√15/7
Note that both values of k give the same solution y = cos(√15/7 t) since cosine is even.
Answer: he invested $46062.5 at 6% and $23031.25 at 10%
Step-by-step explanation:
Let x represent the amount which he invested in the account paying 6% interest.
Let y represent the amount which he invested in the account paying 10% interest.
He puts twice as much in the lower-yielding account because it is less risky.. This means that
x = 2y
The formula for determining simple interest is expressed as
I = PRT/100
Considering the account paying 6% interest,
P = $x
T = 1 year
R = 6℅
I = (x × 6 × 1)/100 = 0.06x
Considering the account paying 10% interest,
P = $y
T = 1 year
R = 10℅
I = (y × 10 × 1)/100 = 0.1y
His annual interest is $7370dollars. it means that
0.06x + 0.2y = 7370 - - - - - - - - - -1
Substituting x = 2y into equation 1, it becomes
0.06 × 2y + 0.2y = 7370
0.12y + 0.2y = 7370
0.32y = 7370
y = 7370/0.32
y = $23031.25
x = 2 × 23031.25
x = 46062.5
The slope is 3 and y-intercept is 4
y=mx+b
