Mark the correct A. monotonically increasing

B. monotonically decreasing

C. not monotonic

D. constant

Formula:- (i) The necessary and sufficient condition for differentiable function defined on (a,b) to be strictly decreading on (a,b) is that f’(x)<0 for all x(a,b)

Given:-

f(x)=2(x-1)+3(2-x)

f(x)=-x+4

Therefore f’(x) <0

Hence decreasing function