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
Negative times a Negative = Positive
Positive times a Positive = Positive
Negative times a Positive = Negative
Positive times a Negative = Negative
Option A:
Negative * Positive * Negative * Positive
Negative * Negative * Positive
Positive * Positive
Positive
Option B:
Anything times 0 is 0, this is incorrect.
Option C:
Negative * Negative * Negative * Negative
Positive * Negative * Negative
Negative * Negative
Positive
Option D:
Negative * Positive * Negative * Negative
Negative * Negative * Negative
Positive * Negative
Negative
Therefore your answer is D.
Answer:
4
Step-by-step explanation: This one is easy if you have 6 groups of ones then times it by 4 and you will get 24.
Answer:
5.31x=9.28-6.65
5.31x=2.63
×=2.63/5.31
x=<u>2</u><u>.</u><u>63</u>
5.31
Answer: WHY MUST I CRYYYYYYY
Step-by-step explanation:
