The tutor explores how to detect and solve exact differential equations with a very simple example. When a differential equation of the form P(x,y) +Q(x,y)y’ = 0 results from the implicit differentiation of an original equation F(x,y)=c, the equation P(x,y) …
Differential equations: exact differential equation Read more »
The tutor explains the idea of odd function vs even function. An odd function is one that gives the opposite output for -x as for x: f(x) odd, then f(-x) = -f(x) x3 and sinx are both odd functions: (-2)3=-8, …
Math: what is an odd function? What is an even function? Read more »
The tutor shows how to easily solve a two-variable linear system with the amazing Sharp el-520w. Let’s imagine you’re posed the following problem: Solve the linear system: (2/3)x – (1/5)y = 2 -4x + 3y = 6 With the Sharp …
Math: solving a system of linear equations in 2 variables with the Sharp el-520w Read more »
The tutor shows absolute value on the Sharp el-520w. As I mentioned in yesterday’s post, absolute value of x, commonly written |x|, can be defined as follows: I can’t find a dedicated absolute value function on the Sharp el-520w; however, …
Math: solving an absolute value equation with the Sharp el-520w equation solver Read more »
The tutor defines absolute value in two ways. The absolute value of x is normally written as |x|; a calculator might call it abs(x) but show it either way. It can be defined as follows: x = { x, x≥0 …
The tutor continues about polynomial long division. I put across the main idea of polynomial long division in my Sept 24 post. What if the polynomial is missing a power of x: for example, like so In such a case, …
Math: polynomial long division: when to add a 0 (missing power of x) Read more »
The tutor shows an example of how to divide a polynomial by a binomial. Long division with polynomials is appreciated by math teachers, but few others. What follows is an illustrated example of how to do it. A simple polynomial …
The tutor tells where the comma is on the Staples BD-6120G. With the Staples BD-6120G, finding the comma took me a few minutes. It’s a blue speck just above the left corner of the hyp key. You would enter a …
Calculator usage: Where is the comma on the Staples BD-6120G? (I’ll tell you:) Read more »
The tutor introduces Fermat’s Theorem with a first example. Fermat’s Theorem states that, for a prime number p and a number b not a multiple of p, bp-1 ≡ 1 (mod p). (See my post here for a working definition …
The tutor continues about lists on the TI-83 Plus. I began about lists on the TI-83 Plus back in my post from January 24, 2015. Now I want to continue. My favourite way to enter a list is from the …
TI-83 Plus: more about creating and editing lists Read more »