MA121 Exam 1 Questions With Clear Solutions
Revenue function Correct Answer - R(x)=xp(x), x= number of units, p(x)
price demand
Profit function Correct Answer - P(x)=R(x)-C(x), c= cost function
To find x coordinates of break even function Correct Answer - Quadratic
formula must be applied: ax^2 + bx + c = 0; x1, x2 = jumbo quad
Where does profit and loss occur Correct Answer - Profit occurs (x1, x2),
loss occurs [0, x1) U (x2, 100] (example numbers)
Quadratic jumbo equation Correct Answer - x1, x2 = (-b +/- root of b^2 -
4ac) / 2a
Compound interest formula Correct Answer - A=P(1 + r/m)^mt
Continuous compound interest formula Correct Answer - A=Pe^rt
Vertex formula Correct Answer - -b/2a
Vertex form Correct Answer - F(x) = a(x-h) + k ; vertex (h, k)
Sometimes need to complete the square, also sometimes need time line with
pos neg functions for sign behavior
, To find x coordinates of break even points Correct Answer - P(x) = 0 , use
quadratic formula x1, x2
To find max profit and max revenue Correct Answer - Computer vertex of
each point separately
For a one sided limit where constant / 0 Correct Answer - +/- infinity
How to know + / - infinity Correct Answer - Does it go to 0 positively or
negatively (make a time line)
Vertical line test Correct Answer - A test used to determine whether a
relation is a function
Horizontal line test Correct Answer - For 1-1 functions
Only invertible functions Correct Answer - 1-1 functions
slope-intercept form Correct Answer - y=mx+b, where m is the slope and b
is the y-intercept of the line.
point slope form Correct Answer - y-y1=m(x-x1)
Revenue function Correct Answer - R(x)=xp(x), x= number of units, p(x)
price demand
Profit function Correct Answer - P(x)=R(x)-C(x), c= cost function
To find x coordinates of break even function Correct Answer - Quadratic
formula must be applied: ax^2 + bx + c = 0; x1, x2 = jumbo quad
Where does profit and loss occur Correct Answer - Profit occurs (x1, x2),
loss occurs [0, x1) U (x2, 100] (example numbers)
Quadratic jumbo equation Correct Answer - x1, x2 = (-b +/- root of b^2 -
4ac) / 2a
Compound interest formula Correct Answer - A=P(1 + r/m)^mt
Continuous compound interest formula Correct Answer - A=Pe^rt
Vertex formula Correct Answer - -b/2a
Vertex form Correct Answer - F(x) = a(x-h) + k ; vertex (h, k)
Sometimes need to complete the square, also sometimes need time line with
pos neg functions for sign behavior
, To find x coordinates of break even points Correct Answer - P(x) = 0 , use
quadratic formula x1, x2
To find max profit and max revenue Correct Answer - Computer vertex of
each point separately
For a one sided limit where constant / 0 Correct Answer - +/- infinity
How to know + / - infinity Correct Answer - Does it go to 0 positively or
negatively (make a time line)
Vertical line test Correct Answer - A test used to determine whether a
relation is a function
Horizontal line test Correct Answer - For 1-1 functions
Only invertible functions Correct Answer - 1-1 functions
slope-intercept form Correct Answer - y=mx+b, where m is the slope and b
is the y-intercept of the line.
point slope form Correct Answer - y-y1=m(x-x1)
