Identify Indeterminate Forms: Rewrite the limit expression to identify indeterminate forms. limx→0x−sinxex−e−x−2x
Check Substitution Result: Check for indeterminate form by substituting x=0.(0−0)(1−1−0)=00, which is an indeterminate form.
Apply L'Hôpital's Rule: Apply L'Hôpital's Rule since we have an indeterminate form of 0/0. Differentiate the numerator and denominator separately. Numerator derivative: dxd(ex)−dxd(e−x)−dxd(2x)=ex+e−x−2. Denominator derivative: dxd(x)−dxd(sinx)=1−cosx.
Rewrite Using Derivatives: Rewrite the limit using the derivatives.limx→01−cosxex+e−x−2
Substitute and Reevaluate: Substitute x=0 into the new expression.(e0+e0−2)/(1−cos(0))=(1+1−2)/(1−1)=0/0.We still have an indeterminate form, so apply L'Hôpital's Rule again.
Differentiate Again: Differentiate the numerator and denominator again.Numerator derivative: dxd(ex+e−x−2)=ex−e−x.Denominator derivative: dxd(1−cosx)=sinx.
Rewrite Using New Derivatives: Rewrite the limit using the new derivatives. limx→0sinxex−e−x
Substitute and Reevaluate: Substitute x=0 into the new expression.(e0−e0)/sin(0)=(1−1)/0.This is undefined, which means there's a mistake in the previous steps.
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