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Question
hi i am very new to calculus 1 please could you help me with these problems
lim 7^3-3^2+x (2) lim 2x^4-3x (3) lim x-15
xto infinity x to infinity x to infinity
___________ _____________ _____________
8x-7x^3-2x^2 5x^2-12 3x^2-5x-6
Hellow Maria ,
Let's solve it step by step :
7x^3-3x^2+x
Lim ------------ = ?
x->∞ 8x-7x^3-2x^2
The trick here is divide all the expressions by the max power of x :
7x^3-3x^2+x
------------ =
8x-7x^3-2x^2
7-(3/x)+(1/x²)
--------------
(8/x²)-7-(2/x)
Therfore :
7-(3/x)+(1/x²)
Lim -------------- =
x->∞ (8/x²)-7-(2/x)
7-(3/∞)+(1/∞²)
-------------- and we know that 1/∞ =0 . Therefore :
(8/∞²)-7-(2/∞)
The limit is :
7-(0)+(0)
-------------- = 7/7 = 1
(0)-7-(0)
& like this method you do the rest .
Alon.
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Answers by Expert:
Alon Mandes
Expertise
Kind of questions I can answer : Limits, Derivatives, Integration, Implicit functions, continuousity, differentiation ,Extremum problems, Lagrange multipliers, Gradients, Surface integrals, Multi variables functions ,Multi variables Integrals,Complex variables ,Complex functions, Curves, Trajectory integrals & Vector analyse,Divergence,Rotor & word problems. Kind of question I can't answer : Economics,Combinatorics,infinite series & convergence ,Statistics & Probabilities .
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