Subtle Differences of Studying Permutations and Combinations

According to Thomas & Pirnot (2014), to select r objects from the set of n objects and calculate the number of selections if there is no interest in the order of those objects, P (n, r) ** It must be divided by r! . I will officially explain. Calculate the formula for C (n, r). If you select r objects from a set of n objects, you are taking r at once and forming a combination of n objects. The symbol C (n, r) represents the number of such combinations (Thomas & Pirnot, (2014), p. 626). Thomas & Pirnot (2014) explains the basic aggregation principle (FCP) as follows. If you want to perform a series of tasks, the first task can be executed in some way, the second task can be executed with b.

Arrange and combine: To place n different items, take n (n ≤ n) at a time. The arrangement of n items has not changed completely. Repeat placement (except circular placement). Use r different combinations at once (r≤n). The combination of n items is completely different. Basic properties Placed and combined problem objects, textures related to architecture and build environment. Interprets image artifacts and visualizes 3D objects from 2D drawings. Visualize various aspects of 3D objects. Analytical reasoning, mental intelligence (visual, digital, language), general perceptions of domestic and foreign architects, famous architectural work

Combinations and placement have somewhat different meanings. Combinations are various ways to select n objects from a group, but the sequence of events is not important. Let's call these 1 and 2 from the set of three objects. For example, if you are asked to select the number of ways to select from three to two objects, there are three combinations of 12, 23, 13 from each pair. The order is not important. On the other hand, positions are taken into account in this arrangement. Therefore, using the example above, there are 6 permutations. An easier way to compute a larger collection is to use Equation 1.