## Welcome to H3 Maths

Blog Support for Growing Mathematicians

## Archive for September, 2014

### Black Holes – Mathematically Impossible?

September29

“Black Holes — the most dense objects in the universe that do not even let light escape — do not exist, a physics professor in the US has claimed. Laura Mersini-Houghton at University of North Carolina at Chapel Hill in the College of Arts and Sciences, has proven, mathematically, that black holes can never come into being […]

by posted under Uncategorized | tagged under , , , ,  |  Comments Off on Black Holes – Mathematically Impossible?

### Math and Science = Harry Potter Invisible Cloak

September28

University researchers have come up with a very low cost cloaking device. This use of lenses bends light around objects and makes them invisible, even when viewed from different angles. Now, think about some of the uses of this technology!

by posted under Uncategorized | tagged under , , ,  |  Comments Off on Math and Science = Harry Potter Invisible Cloak

### There is always enough time for math…

September25

by posted under Uncategorized | tagged under , ,  |  Comments Off on There is always enough time for math…

### 1 = 3 What? Call the Math Doctor!

September24

Yes, you read about it here on H3! In Year 10 you learn the basic laws when working with logarithms. Do you remember what a logarithm is? If not, read more here from an earlier post. Then, take one of these laws (the log of a power) and you can prove, in about as many […]

by posted under Uncategorized | tagged under , , , , , , ,  |  Comments Off on 1 = 3 What? Call the Math Doctor!

### Mathmataria – old Math collectables

September23

Yes, almost-the-latest garage sale craze is looking for old Mathematical toys. This one below is a “mechanical flash card” machine for Mathematics (patented in the 1940s!). Pull the handle and the drum rotates to bring up random sums. The answers are under the black strip at the top. Actually, we have used this with our […]

by posted under Uncategorized | tagged under , ,  |  Comments Off on Mathmataria – old Math collectables

### Maths Takes You Places

September22

There seems to be a “Careers in Math” theme running through the last few posts. This one is no different and takes a look at some specific careers that have taken paths shaped by (you guessed it) Mathematics! Click on the image below to find out more from http://mathsofplanetearth.org.au, hosted by The Australian Mathematical Sciences […]

by posted under Uncategorized | tagged under , , ,  |  Comments Off on Maths Takes You Places

### Crippling Cost of Doubling Every Week

September17

A recent news article looked at the cost of of fines which the US Justice Department threatened against Yahoo if it didn’t comply with a request for user data back in 2008. News coverage of the case, for which documents were recently, reported the proposed fines as \$250,000 a day. But there was also a […]

by posted under Uncategorized | tagged under , ,  |  Comments Off on Crippling Cost of Doubling Every Week

### Using Geometry to Speed Date

September16

Yes, the Bowerbird is a great fan of the geometric speed dating. “While most bowerbirds embellish their “love nests” with bright, shiny baubles, the great bowerbird’s decor is comparatively bland: an avenue of sticks leading to a pair of courts garnished with mostly gray-to-white objects like pebbles, shells, and bones. Biologists John Endler and Laura […]

by posted under Uncategorized | tagged under , , ,  |  Comments Off on Using Geometry to Speed Date

### Substituting – may the Algebraic Force be with you!

September16

This H3 ppt is free for download and distribution and is an introduction to the power of Algebraic Substitution – a critical skill for doing well in senior math. Here is the ppt: Substituting into an equation

by posted under Uncategorized | tagged under ,  |  Comments Off on Substituting – may the Algebraic Force be with you!

### Infinity

September10

From Scientific American comes some wonderful designs, based on the locus (path) of moving dots. Click on them to activate.

by posted under Uncategorized | Comments Off on Infinity

#### Post Support

The graph on the left (Coronavirus) is for a time period of 30 days, while the one on the right (SARS) is for 8 months! Very poor graphical comparison and hardly relevant, unless it is attempting to downplay the seriousness of the coronavirus?

10 x 9 x 8 + (7 + 6) x 5 x 4 x (3 + 2) x 1 = 2020

NCEA Level 2 Algebra Problem. Using the information given, the shaded area = 9, that is:
y(y-8) = 9 –> y.y – 8y – 9 =0
–> (y-9)(y+1) = 0, therefore y = 9 (can’t have a distance of – 1 for the other solution for y)
Using the top and bottom of the rectangle,
x = (y-8)(y+2) = (9-8)(9+2) = 11
but, the left side = (x-4) = 11-4 = 7, but rhs = y+? = 9+?, which is greater than the value of the opp. side??
[I think that the left had side was a mistake and should have read (x+4)?]