Answer:
(1 cm)cos3πt
Step-by-step explanation:
Since the piston starts at its maximal height and returns to its maximal height three times evert 2 seconds, it is modelled by a cosine functions, since a cosine function starts at its maximum point. So, its height h = Acos2πft
where A = amplitude of the oscillation and f = frequency of oscillation and t = time of propagation of oscillation.
Now, since the piston rises in such a way that it returns to the maximal height three times every two seconds, its frequency, f = number of oscillations/time taken for oscillation where number of oscillations = 3 and time taken for oscillations = 2 s
So, f = 3/2 s =1.5 /s = 1.5 Hz
Also, since the the piston moves between 3 cm and 5 cm, the distance between its maximum displacement(crest) of 5 cm and minimum displacement(trough) of 3 cm is H = 5 cm - 3 cm = 2 cm. So its amplitude, A = H/2 = 2 cm/2 = 1 cm
h = Acos2πft
= (1 cm)cos2π(1.5Hz)t
= (1 cm)cos3πt
Solution: The missing reason in Step 8 is substitution of 
.
Explanation:
The given steps are used to prove the formula for law of cosines.
From step 5 it is noticed that our equation is
..... (1)
From step 7 it is noticed that the value of 
is 
.
So by substituting for in equation (1) we get the equation of step 8, i.e.,
Hence, the missing reason in Step 8 is substitution of .
Answer:
Simplifying
x = -25
Step-by-step explanation:
Reorder the terms:
10x + -6(5 + 2x) = 20
10x + (5 * -6 + 2x * -6) = 20
10x + (-30 + -12x) = 20
Reorder the terms:
-30 + 10x + -12x = 20
Combine like terms: 10x + -12x = -2x
-30 + -2x = 20
Solving
-30 + -2x = 20
Solving for variable 'x'.
Move all terms containing x to the left, all other terms to the right.
Add '30' to each side of the equation.
-30 + 30 + -2x = 20 + 30
Combine like terms: -30 + 30 = 0
0 + -2x = 20 + 30
-2x = 20 + 30
Combine like terms: 20 + 30 = 50
-2x = 50
Divide each side by '-2'.
x = -25
Go up on the graph (y axis) and you need to go down 3 on the y axis and go to the right one and repeat. let me know if you want me to draw it out!
