[PDF] MATH1921/1931 - Solutions to Tutorial for Week 4 - Semester 1 2018

What is an injective and surjective function?

A bijection is a function that is both injective and surjective. This means that every element of the codomain appears exactly once. What is the difference between an injective function and a surjective function? An injective function is a function where every element of the codomain appears at most once.

How to calculate the total number of surjective functions?

First one is with your current approach and using inclusion-exclusion, so you need to count the number of functions that misses 1 element, lets call it S 1 which is equal to ( 3 1) 2 5 = 96, and the number of functions that miss 2 elements, call it S 3, which is ( 3 2) 1 5 = 3. And now the total number of surjective functions is 3 5 ? 96 + 3 = 150.

What are some adjectives for calculator?

— Adjectives for calculator: electronic, scientific, programmable, financial, held, simple, mechanical, first, small, graphic, automatic, more ... — People also search for: worksheet, spreadsheet, abacus, calculations, graphs, printout, logarithm, widget, voltmeter, more ... Commonly used words are shown in bold. Rare words are dimmed.

How is well injectivity calculated?

The expected injectivity can be calculated on the basis of routine core analysis, special core analysis and/or log data, and the existing production wells’ productivity; however, well injectivity often is not known until water actually is injected into the reservoir interval.