∵f'(0)=1
∴limx→0[f(x)-f(-x)]/x
=limx→0[f(x)-f(0)+f(0)-f(-x)]/x
=limx→0[f(x)-f(0)]/x+limx→0[f(0)-f(-x)]/x
=f'(0)+limx→0[f(-x)-f(0)]/(-x)
=1+f'(0)
=2
∵f'(0)=1
∴limx→0[f(x)-f(-x)]/x
=limx→0[f(x)-f(0)+f(0)-f(-x)]/x
=limx→0[f(x)-f(0)]/x+limx→0[f(0)-f(-x)]/x
=f'(0)+limx→0[f(-x)-f(0)]/(-x)
=1+f'(0)
=2