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
2x+4y=0
3x+y=10
So what we want to do is get y onto one side by itself using whatever equation you like.
So I'm taking 2x+4y=0 and subtracting 4y from both sides
So we end up with
2x=4y
Divide both sides by four
2/4x is 1/2 x
So we get 1/2x=y
Take this and plug it into the other equation
3x+y=10
3x+1/2x=10
Add your like terms
3 1/2x=10
Putting 3 1/2 as a mixed number we get 7/2
So..
7/2x=10
Multiply by the opposite of 7/2 on both sides
Which is 2/7 this will cancel out the left side.
So we end up with
X= 10•2/7
X=20/7
Which is 2 and 6/7 as a mixed number.
Answer:
True!
Step-by-step explanation:
Distributive property
It's not possible nothing but 1 times 5 is the only thing that multiplies to 5 and 1+5 doesn't equal 4