University:
Highline College
Course:
MATHP 141 | Precalculus I Plus Extra Support
Academic year:

2022
Views:

375

Pages:

1
Author:

snowbaby1950sp2

Workshop #23 1. Graph the following and determine if the discriminant is positive, negative or zero. (a) f (x) = 3 − x2 (b) g(x) = (x − 2)2 (c) h(x) = (x − 2)2 + 2 2. A parabola written as f (x) = a(x − h)2 + k is said to be in vertex form. Complete the square to write the following parabolas in vertex form. (a) f (x) = x2 + 6x − 1 (c) h(x) = 7x − x2 + 3 (b) g(x) = 2x2 + 8x (d) k(x) = −3x2 + 6x + 3 3. Find the vertex and axis of symmetry of each parabola from the previous problem. 4. Find the vertex of the parabola y = −2(x + 1)2 − 7. Is this vertex a maximum or minimum? 5. Let x be the side of a rectangle with a 70 inch perimeter. (a) Construct an expression in terms of the variable x which gives the area of the rectangle. (b) Graph the parabola you constructed in part (a). (c) Looking at the graph, which x value would give the largest possible area for the rectangle? (d) What dimensions would the rectangle have to be to achieve the maximum possible area. 6. The revenue for selling x action ﬁgures is given by R(x) = − x2 + 3x 324 how many units need to be sold to maximize the revenue? 7. Graph the inequalities (a) y < x2 (b) y ≥ x2 + 1 (c) y < 4 − x2