Category: Trigonometry
"Published in Newark, California, USA"
Last October 9, 2012, we did the derivation of the Sum and Difference of Two Angles Formula. Right now, we will derive the formulas for Double Angle Formula from the formulas of the Sum and Difference of Two Angles Formula.
Let's consider this one,
if θ = ϕ, then
Let's try this one,
if θ = ϕ, then
Category: Arithmetic
"Published in Newark, California, USA"
How do you multiply a three digit number with another three digit number without using a calculator in a shorter way and faster? I will show you a technique. Let's consider this one:
124 x 216
By usual method,
1 2
1 2 4
x 2 1 6
---------------------
1 7 4 4
1 2 4
2 4 8
----------------------
2 6 7 8 4
Now, let's consider the other method which is Mayan Method. In this method, you will use the straight lines and their points of intersection.
For 124, draw 1 line, 2 parallel lines, and then 4 parallel lines that are all parallel to each other.
For 216, draw 2 parallel lines, 1 line, and then 6 parallel lines that are all parallel to each other.
Divide the figure into 5 sections. At each section, count the number of points which are the points of intersection.
Therefore, the answer is 26784.
Category: Arithmetic
"Published in Suisun City, California, USA"
How do you multiply a two digit number with another two digit number without using a calculator in a shorter way and faster? I will show you a technique. Let's consider this one:
23 x 34
By usual method,
1
2 3
x 3 4
---------------
1 9 2
6 9
---------------
7 8 2
Now, let's consider the other method which is Mayan Method. In this method, you will use the straight lines and their points of intersection.
For 23, draw 2 parallel lines and then another 3 parallel lines that are all parallel to each other.
For 34, draw 3 parallel lines and then another 4 parallel lines that are parallel to each other.
Divide the figure into three sections. At each section, count the number of points which are the points of intersection.
Therefore, the answer is 782.
