Identify the form: Identify the form of the limit.We need to find the limit of the function as x approaches 2. Let's first substitute x=2 into the function to see if we can directly evaluate the limit.limx→2x−2x4−4x3+4x2=2−224−4⋅23+4⋅22=016−32+16=00This is an indeterminate form, so we cannot directly evaluate the limit.
Factor the numerator: Factor the numerator.Since we have an indeterminate form, we should try to simplify the expression. The numerator is a polynomial that can be factored, especially since we see a common pattern (x2−2x)2.Let's factor the numerator:x4−4x3+4x2=(x2)2−2⋅2⋅x⋅x2+(2x)2=(x2−2x)2Now we have:limx→2(x−2)(x2−2x)2
Factor out a common term: Factor out a common term.We notice that the numerator is a perfect square and can be written as (x−2)2∗(x+2)2. Since we have an (x−2) term in the denominator, we can cancel out one (x−2) term from the numerator and the denominator.limx→2(x−2)2∗(x+2)2/(x−2)= limx→2(x−2)(x+2)2
Evaluate the limit: Evaluate the limit.Now that we have canceled the common term, we can directly substitute x=2 into the remaining expression to find the limit.limx→2(x−2)(x+2)2=(2−2)(2+2)2=0×42=0
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