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
To determine the effect of changing the diameter of a sphere to its volume, we would need to know the formula for the volume of a sphere which is V = 4πr³/3 where r is half of the diameter. As you can see, there is a direct relationship.
r1 = d1/2
r2 = d2/2 = 2d1/2 = d1
V2/V1 = (4πd1³/3) / (4π(d1/2)³/3)
V2/V1 = 8
Therefore, the volume of the sphere would be 8 times the original volume.
Answer:
1. Read through the problem and figure out what it's about.
Represent numbers you don't know with variables.
Translate the problem into a mathematical expression.
Solve the problem.
Check your work.
Step-by-step explanation:
So you need to find the slope and the y- intercept. So, the slope is always the coefficient on the x. In this case it is 4. The y-intercept is the other number. In this case it is -5. So the slope is 4 and the y-intercept is -5. On your graph (the y axis) find -5. Then you go up 4 and to the right 1 because of four were a fraction it would be 4/1. Keep going up four and right one a couple times. Then reverse it. Go down 4 left 1. That as a fraction would look like -4/-1. Then connect your points and make it a line!
Answer:
a.
Step-by-step explanation:
