Answer:
A. v(t) = sin (2πft + π/2) = A cos (2πft)
Step-by-step explanation:
According to trigonometry friction, the following relationship are true;
Sin(A+B) = sinAcosB + cosAsinB
We will be using this relationship to check which option is true.
Wave equation is represented as shown;
y(t) = Asin(2πft±theta)
For positive displacement,
y(t) = Asin(2πft+theta)
If theta = π/2
y(t) = Asin(2πft+π/2)
y(t) = A[ sin 2πftcosπ/2 + cos2πft sin π/2]
Since sinπ/2 = 1 and cos (π/2) = 0
y(t) = A[ sin 2πft (0)+ cos2πft (1)]
y(t) = A[0+ cos2πft]
y(t) = Acos2πft
Hence the expression that is true is expressed as;
v(t) = Asin(2πft+π/2) = Acos2πft
Answer:
$ 720
Step-by-step explanation:
Normal time $ 15
Overtime: 15 x 1/3 = $5 + $15 = $20
(40 x 15) + (6 x 20) = 600 + 120
Answer: All four runners ran .96 seconds
Step-by-step explanation: The total time of the four runners, divided by the amount of runners.
3.86/4= .965
Answer:
2) Add 21 to both sides
Step-by-step explanation:
When solving 
for 
, our goal to isolate such that we have set equal to something.
Therefore, we want to start by adding 21 to both sides. This leaves us with 
and we are one step closer to isolating .
Answer:
2.559 × 10 to the 1st power
Step-by-step explanation:
using a SNC
