<P> Although an ALU can be designed to perform complex functions , the resulting higher circuit complexity , cost , power consumption and larger size makes this impractical in many cases . Consequently , ALUs are often limited to simple functions that can be executed at very high speeds ( i.e. , very short propagation delays ) , and the external processor circuitry is responsible for performing complex functions by orchestrating a sequence of simpler ALU operations . </P>
what is the use of alu in computer
simple functions that can be executed at very high speeds