If f(x)=−3x+2,x<112x2+7,x≥1, then which of the following is not true
f'(1+)=1
f'(1−)=−3
f'(1−)=f'(1+)=1
is not differentiable at x=1
f′(X)=−3, if x<1x, if x≥1⇒f11−=−3,f11+=1