Domain and Range Review (Days 20-23)

DOMAIN AND RANGE

First Verse: (Draw a function like f (x) = x + 4 over the given domain.)
DIXI, what's our domain?
1 less than x less than 5.
And ROYD, what is our range now?
5 less than y less than 9.

Second Verse: (Draw a function like f (x) = 6x - x^2 over the given domain.)
DIXI, what's our domain?
1 less than x less than 5.
And ROYD, what is our range now?
5 less than y less than equal to 9.

Third Verse: (Draw a function like f (x) = 2^x.)
DIXI, what's our domain?
All real numbers it contains.
And ROYD, what is our range now?
y greater than 0, for a change.

The mnemonics in this song come from Sarah Carter (DIXI-ROYD).

This is the second song that I'm writing in 10EDL, our main scale for September and October. The first few 10EDL songs will be written in AAA format, with verses only.

Here's a link to the Mocha code for the song:

https://www.haplessgenius.com/mocha/

10 N=8

20 FOR V=1 TO 3

30 FOR X=1 TO 25

40 READ A,T

50 SOUND 261-N*A,T

60 NEXT X

70 RESTORE

80 NEXT V

90 END

100 DATA 7,2,7,2,9,6,8,6,10,8

110 DATA 8,8,9,4,9,2,8,2,9,4

120 DATA 8,4,7,12,6,4,8,2,6,2

130 DATA 5,4,6,4,9,4,5,8,5,8

140 DATA 5,4,9,4,5,4,6,4,5,16

As usual, click on Sound before you RUN the program.

For this song, I simply sing through each verse as the music plays, with no repeated lines. The chords are a bit tricky to play, though, now that Degree 7 (F#) appears more prominently throughout the song, including the first two notes. The first three notes are F#-F#-D so our D7 chord from yesterday's song fits somewhat. But I might find better ways to chord our 10EDL songs (or just cheat and switch to G to make it a true pentatonic melody).

Also, another thing about having a simple scale like 10EDL is the limited selection -- the last five notes already sound like the first four notes of yesterday's song! As I perform it today, I instead insert Degree 4 (a high E) instead of the Degree 9 (a low D) listed in the Mocha code above -- and this is despite my saying earlier that I wouldn't sing that high.

So once again, this is a work in progress, and I might find ways to improve this song.