‌A={1,2,3,4} ‌B={1,4,9,16} Total number of functions =44 Total number of one-one functions =4 ! Total number of many one functions =44−4!=232 Total number of many-one functions in which 1∉f(A)=3×3×3×3=81 ∴ Total number of many one functions 1∉f(A) ‌=232−81 ‌=151