To find the values of n and m, we first determine the value of p, which is defined as the left-hand derivative of ∣x−1∣ at x=1.
By the definition of the left-hand derivative:
p=limh→0−h∣(1+h)−1∣−∣1−1∣=limh→0−h∣h∣
Since h<0, we have ∣h∣=−h. Therefore:
p=limh→0−h−h=−1
Now, we evaluate the given limit:
limx→1+g(x)=limx→1+logcosm(x−1)(x−1)n
Let t=x−1. As x→1+, t→0+. Since cost>0 for t∈(0,1), we can rewrite the logarithmic term using the power property of logarithms:
logcosm(t)=mlog(cost)
Thus, the limit becomes:
limt→0+mlog(cost)tn
Using the Taylor series expansion of cost near t=0:
cost=1−2t2+O(t4)
Applying the expansion of log(1+u) for u=−2t2+O(t4):
log(cost)=log(1−2t2+O(t4))=−2t2+O(t4)
Substituting this back into the limit:
limt→0+m(−2t2+O(t4))tn=limt→0+−m2⋅t2(1+O(t2))tn=limt→0+(−m2)tn−2
For the limit to exist and equal the non-zero finite value p=−1:
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The exponent of t must be zero:
n−2=0⟹n=2
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The coefficient must equal p:
−m2=−1⟹m=2
Thus, we have n=2 and m=2.
Therefore, the correct option is C.