Let
C-----------------
> charges for the purchases to the credit card
<span>r-------------------
> the interest rate </span>
X------------------
> total cost of the purchase
we know that
C=4120
r= 22.45%=0.2245
X=C*(1+r)
substituting the values in the formula
X=(4120)*(1+0.2245)=
(4120)*(1.2245)=5044.94
the answer is
$5044.94
Use area formula (length x width)
42 x 25.5 = 1,071
Divide by total cost of wall paper
1,071/771.25 = $1.38 per square foot
[This question is such you will not understand a thing without your involvement as well. So follow my step and check by yourself]
First plot both functions on graph (this you gotta do yourself and check because only then you will learn)
How you plot the function?
f(x)=-3x³+5x-5
Put y=f(x)
y=-3x³+5x-5➡eqn(1)
So note the corresponding values of y on putting different values of x in that function.
I'll show u:
When x=0,y=-5 [calculate yourself it's easy just put x=0 and find value of y in eqn(1)]
Similarly,
x=1,y=-3
x=2,y=-19
[Similarly put x=-1,-2..and find corresponding y]
So you got points (0,-5),(1,-3),(2,-19)...plot these points and you have successfully plotted f(x).
Same process for plotting function g(x)....at least 6 points must be plotted.
❇After plotting f(x) and g(x):
1)check by yourself if they have same y-intercept (which is the distance between origin and the point of intersection of y-axis and the curve/line)
2) To check if they have same behavior or not,
increase the value of x[ie,1,2,3...] and note the corresponding value of y in function f(x) . Then decrease value of x[ie,-1,-2,-3..] and note corresponding value of y [note that y means function or f(x)]
Suppose f(x) has following end behavior:
When x increases f(x) tends to decrease
and when x decreases f(x) tends to increase
Now find end behavior of g(x) also..and if above end behavior matches with g(x), they will have same end behavior.
3) check by yourself by looking in plotted graphs of f(x) and g(x) whether they have at least one x-intercept or not.
4)g(x) is even function but f(x) is odd function.
So, g(x) is symmetrical over y-axis but f(x) is not.
5) Actually most of the algebraic polynomial functions don't show periodicity(but trigonometric and exponential function do). You can check by yourself by looking in plotted graph. If graph seems to be repeating same behavior it is periodic otherwise not. I am sure the given functions are not periodic. {Plz google periodic function if you want to know more}
ok
