Boo Math

   Determinan Matriks  Salah satu bagian paling penting dari pembahasan materi matriks adalah cara menghitung determinan matriks, invers matriks, dan sifat-sifatnya. Sobat perlu meneguasai dasar cara menentukan determinan matriks, invers matriks, dan sifat-sifatnya karena akan sangat dibutuhkan untuk membantu perhitungan matriks dengan tipe soal tingkat lanjut.  Untuk pertama, sobat akan dikenalkan melalui bagian yang paling sederhana yaitu mencari determinan matriks dengan ordo 2 x 2. Untuk tingkat SMA, ulasan mengenai determinan matriks biasanya melibatkan matriks dengan ordo 2 x 2. Namun, materi determinan matriks dengan ukuran lebih besar juga sering diulas. Hanya saja tidak sesering determinan matriks ordo 2 x 2. Cara menentukan determinan matriks untuk orde lebih besar dari 3 x 3 lebih rumit dari cara menentukan determinan matriks ordo 2 x 2. Menentukan nilai invers matriks ordo 2 x 2 cukup mudah dilakukan. Sedangkan cara menentukan inver...

Perpangkatan Bilangan Bulat Di sekolah dasar pernah dijelaskan mengenai pengertian kuadrat suatu bilangan. Kuadrat atau pangkat dua suatu bilangan artinya mengalikan suatu bilangan dengan bilangan itu sendiri. Sehingga perpangkatan suatu bilangan artinya perkalian berulang dengan bilangan yang sama. perhatikan perpangkatan bilangan pokok 2 berikut. 2¹ = 2 2 ² = 2 x 2 = 4                                 ( 2² dibaca 2 kuadrat atau 2 pangkat 2 0 2³ = 2 x 2 x 2 = 8                          ( 2³ dibaca 2 pangkat 3 ) 2ⁿ = 2 x 2 x 2 x … x 2                    ( 2ⁿ dibaca 2 pangkat n ) nkali secara umum dapat dituliskan sebagai berikut. untuk sembarang bilangan bulat p dan bilangan positif n, berlaku keterangan : p = bilangan pokok n = disebut pangkat (eksponen ) u...

                                          Box plot A box  and whisker plot—also called a box plot—displays the five-number summary of a set of data. The five-number summary is the minimum, first quartile, median, third quartile, and maximum. In a box plot, we draw a box from the first quartile to the third quartile. A vertical line goes through the box at the median. The whiskers go from each quartile to the minimum or maximum.

Correlation Coefficient  A number that is a measure of the strength and direction of the correlation between two variables. Correlation coefficients are expressed using the variable r, where r is between 1 and –1, inclusive. The closer r is to 1 or –1, the less scattered the points are and the stronger the relationship. Only data points with a scatterplot which is a perfectly straight line can have r = –1 or r = 1. When r < 0 the data have a negative association, and when r > 0 the data have a positive association.

FREQUENCY  The frequency of a particular data value is the number of times the data value occurs. For example, if four students have a score of 80 in mathematics, and then the score of 80 is said to have a frequency of 4.  The frequency of a data value is often represented by f. The marks awarded for an assignment set for a Year 8 class of 20 students were as follows:       6     7     5     7     7     8     7     6     9     7       4     10   6     8     8     9     5     6     4     8

COMPOSITE FIGURE  A figure (or shape) that can be divided into more than one of the basic figures is said to be a composite figure (or shape). For example, figure ABCD is a composite figure as it consists of two basic figures.  That is, a figure is formed by a rectangle and triangle as shown below. The area of a composite figure is calculated by dividing the composite figure into basic figures and then using the relevant area formula for each basic figure.

System of Linear Equation  A Linear Equation is an equation for a line. A linear equation is not always in the form y = 3.5 − 0.5x, It can also be like y = 0.5(7 − x) Or like y + 0.5x = 3.5 Or like y + 0.5x − 3.5 = 0 and more. (Note: those are all the same linear equation!) A System of Linear Equations is when we have two or more linear equations working together. it's a race! You can run 0.2 km every minute. The Horse can run 0.5 km every minute. But it takes 6 minutes to saddle the horse. How far can you get before the horse catches you? We can make two equations (d=distance in km, t=time in minutes) You run at 0.2km every minute, so d = 0.2t The horse runs at 0.5 km per minute, but we take 6 off its time: d = 0.5(t−6) So we have a system of equations (that are linear): d = 0.2t d = 0.5(t−6) Do you see how the horse starts at 6 minutes, but then runs faster? It seems you get caught after 10 minutes ... you only got 2 km away. Run faster next time.