When given two points, use point-slope form
When given a point and the intercept, use slope-intercept form.
When given a point and the slope, use point slope form.
The answer is C. 7.1 feet.
I hope this helps.
To find concavity we need to find the second derivative.
Use quotient rule to find f'(x)=4/(x+3)^2
Then use chain rule to find f''(x)=-8/(x+3)^3
To find potential inflection points, we need to find all x values where the second derivative is equal to 0 or is undefined.
Set the numerator and denominator equal to 0 and solve.
(x+3)^3=0
x+3=0
x= -3
Now plug a value less than -3 and greater than -3 into the second derivative to find where the concavity is upward (positive number).
Since f''(-4) is positive, that means that f(x) is concave up on the interval (-infinity, -3).
The sinusoid makes a complete oscillation (i.e. 360°) every 3 seconds. So, in one second it makes 1/3 of a turn, leading to 360°/3 = 120°.
So, the correct answer is the last one.
