Plug in x=0: First, let's try to plug in x=0 directly and see what happens.x→0limx−sinxex−e−x−2x=0−sin0e0−e0−2⋅0=0−01−1−0=00We get an indeterminate form, so we need to use L'Hôpital's Rule.
Apply L'Hôpital's Rule: L'Hôpital's Rule says that if we have an indeterminate form of 0/0 or ∞/∞, we can take the derivative of the numerator and the denominator separately and then take the limit.So, let's find the derivative of the numerator: dxd(ex−e−x−2x)=ex+e−x−2.
Find derivative of numerator: Now, let's find the derivative of the denominator: dxd(x−sinx)=1−cosx.
Find derivative of denominator: Now we take the limit of the derivatives: limx→01−cosxex+e−x−2. Let's plug in x=0 again: 1−cos0e0+e0−2=1−11+1−2=00. Oops, we got another indeterminate form, so we need to apply L'Hôpital's Rule again.