The tutor shows an example of a typical problem involving a quadratic function. Consider the following problem: A quadratic function has vertex (-7,4) and passes through (-4,10). Find its equation. Solution: Since we are given the vertex, the useful form …
Math: Quadratic functions: finding the equation from two points Read more »
The tutor discusses the exponential growth constant with an example. Let’s imagine a population, initially 100, doubles every 25 hours. To a biologist growing a culture, it’s probably an easy situation to consider. Such a growth pattern would likely be …
F1, F2, F3, and F4 (the arrow keys) are prominent on the Sharp EL-520W; the tutor introduces their use. I’ve always wondered what F1, F2, F3, and F4 do on the Sharp EL-520W. It turns out they can be used …
Calculator usage: Sharp EL-520W: Using F1, F2, F3, F4 Read more »
The tutor shares a recent discovery. Imagine you want to calculate 8/2×4 The answer should be 1, of course: in a fraction, there are unwritten brackets around the numerator and around the denominator. Unless you have a calculator that accepts …
Calculator usage: Sharp EL-520W: multiplication in the denominator Read more »
The tutor covers a day-to-day issue in high school algebra. Consider the following problem: 14=5/(3x) Solution: First, multiply both sides by 3x: 3x(14)=(3x)*5/(3x) The right side is now both divided and multiplied by 3x, so they cancel there: 3x(14)=5 On …
The tutor talks more about how to find the angle in standard position from the reference angle. For my introductory post about this, see here. Let’s imagine you know the reference angle is 71°, but the actual angle is in …
Math: more about angles in standard position and reference angles Read more »
The tutor introduces another way of stating a point location. Back in my Oct 29 post I described angles in standard position and reference angles with a couple of illustrations. The idea relates to polar coordinates. With (x,y) coordinates, which …
The tutor provides a brief hint about using trig functions of angles in degrees on LibreOffice Calc. A person who doesn’t use a spreadsheet very often, probably needs it to work quickly and reliably the rare time they do use …
Spreadsheets: trig functions w/ degrees in LibreOffice Calc Read more »
The tutor offers a quick hint about a derivative that can be tricky. Example: find the derivative of √x Solution: Rewrite √x as x^0.5 Take the derivative using the power rule: (x^0.5)’ = 0.5x^(-0.5) You may want to rewrite, perhaps …
The tutor shares another convenient feature of the Casio fx-260solar. In high school math, you might have to convert between degrees and rads. It’s easy with the Casio fx-260solar; here’s how: Example 1 Convert 60 degrees to rads. Solution: Let’s …
Calculator usage: deg to rad, rad to deg conversion on the Casio fx-260solar Read more »