Answer
a. (a + b) · (c + d)
b. Partial answer: 11∗ = 1·1 = 1, 12∗ = 1·2 = 2, 21/ = 2/1 = 2
Work Step by Step
a. If the expression ab + cd + · in postfix notation is converted
to infix notation, what is the result
. Let $E = {1, 2,*, /}$ and let L be the set of all strings
over $E obtained by writing first a number (1 or 2), then
a second number (1 or 2), which can be the same as the
first one, and finally an operation (* or / where * indicates
multiplication and / indicates division). Then L is
a set of postfix, or reverse Polish, expressions. List all the
elements of L between braces, and evaluate the resulting
expressions.
---a. (a + b) · (c + d)
b. Partial answer: 11∗ = 1·1 = 1, 12∗ = 1·2 = 2, 21/ = 2/1 = 2