Key, 1.1
(1) For the following function:
(a) What is
(b) For what x-values is at the x-intercepts, x = 3 and x = -3
(c) Find the equation of the line which intersects f at x = 1 and x = 3.
Find the two points on f at x = 1: (1, - 8) and (3, 0).
Find the slope of the line containing them: , then pick a point (I’m going with (3, 0) ), and use point-slope form (go ahead and solve for y, too)
(2) Give the average velocity of an object moving along the curve between x = 1 and x = 4.
(3) A test tube is knocked off a tower at the top of a green building. (For the purposes of this experiment the tower is 400 feet above the ground. It’s height after t seconds is .
a) the average speed in the first two seconds of the fall (tip: that’s t = 0 to t = 2).
b) the average speed in the last two seconds of the fall (tip: you must first find the time when said object hits the ground, and count back two seconds).
Hits ground when
So the last two seconds would be between t = 3 and t = 5.
(4) Find the difference quotient of the function:
(a)
(b) (tip: )
(5) Graph the piecewise function:
Yours probably won’t look as spectacular as this:
(6) Let’s say I define a piecewise function
What would the value a have to be for the two pieces to ‘connect’, so that there was no jump in the function?
Soln: The only place where the function could have a jump is at the point where the domain ‘splits’, at x = 1. The two pieces would have to be equal there. So plug 1 into both of them, and solve the equation for a:
(7) Graph the following translates of elementary functions:
(a) Shift root x up 2: (b) inverts, then up 4:
(c) this takes the cube function, and shifts it 1 unit right:
(I don’t really like this graph – stupid computer)
(8) Use the unit circle or standard triangles to evaluate the following:
(a)
(b)
(c) =
(d)