Answer:
(d) -- see attached
Step-by-step explanation:
A graph that shows exponential decay is one that tends toward a horizontal asymptote as x gets large.
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A basic (parent) exponential decay curve is concave upward and tends toward zero as x gets large. The fractional change in any interval is the same as for any other interval of equal size. The curve attached decreases by a factor of 2 when x increases by 1.
Now the width is w.
It's twice as long as wide, so now the length is 2w.
If the length is increased by 4 cm, the length will be 2w + 4.
The width is decreased by 3 cm, so the width will be w - 3.
The are of the new rectangle is 100 cm^2.
area = length * width
area = (2w + 4)(w - 3)
The area of the new rectangle is 100, so we get
(2w + 4)((w - 3) = 100
2w^2 - 6w + 4w - 12 = 100
2w^2 - 2w - 112 = 0
w^2 - w - 56 = 0
(w - 8)(w + 7) = 0
w - 8 = 0 or w + 7 = 0
w = 8 or w = -7
A width cannot be negative, so discard w = -7.
w = 8
The width is 8 cm.
The length is twice the width, so the length is 16 cm.
Hello,
Use the factoration
a^2 - b^2 = (a - b)(a + b)
Then,
x^2 - 81 = x^2 - 9^2
x^2 - 9^2 = ( x - 9).(x + 9)
Then,
Lim (x^2- 81) /(x+9)
= Lim (x -9)(x+9)/(x+9)
Simplity x + 9
Lim (x -9)
Now replace x = -9
Lim ( -9 -9)
Lim -18 = -18
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The second method without using factorization would be to calculate the limit by the hospital rule.
Lim f(x)/g(x) = lim f(x)'/g(x)'
Where,
f(x)' and g(x)' are the derivates.
Let f(x) = x^2 -81
f(x)' = 2x + 0
f(x)' = 2x
Let g(x) = x +9
g(x)' = 1 + 0
g(x)' = 1
Then the Lim stay:
Lim (x^2 -81)/(x+9) = Lim 2x /1
Now replace x = -9
Lim 2×-9 = Lim -18
= -18
Answer:
-1.575, or -1 575/1000, or -1 23/40
Step-by-step explanation:
Simplify the problem slightly by prefacing it with " - " as follows:
334
- ----------- = -1.575 = -1 23/40
212
