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: 6√6
Step-by-step explanation:
√216=
√(36*6)=6√6
Answer:
a=√x3y5 or a=−√x3y5
Step-by-step explanation:
X=5 if you solve the equation 20=8x/2
Answer:
36 miles
Step-by-step explanation:
His entire journey, represented with a diagram, is in the shape of a right angle triangle.
We need to first find the hypotenuse of the triangle, then, add all the sides together:
hyp² = opp² + adj²
hyp² = 9² + 12²
hyp² = 81 + 144 = 225
Find the square root of both sides:
hyp = 15 miles
Therefore, adding the three sides together:
Total distance traveled = 9 + 12 + 15
Total distance traveled = 36 miles
He would ride 36 miles altogether.
