/ ____________ \ / ____________ \ / ____________ \
| / ____ / ___\ | | / ____ / ___\ | | / ____ |
| / 1 \/ 93 | 1 I*\/ 3 | 1 | | / 1 \/ 93 | 1 I*\/ 3 | 1 | | / 1 \/ 93 1 |
a*|a + - 3 / - + ------ *|- - - -------| + -----------------------------------|*|a + - 3 / - + ------ *|- - + -------| + -----------------------------------|*|a + - 3 / - + ------ + -------------------|
| \/ 2 18 \ 2 2 / ____________ | | \/ 2 18 \ 2 2 / ____________ | | \/ 2 18 ____________|
| / ____ / ___\| | / ____ / ___\| | / ____ |
| / 1 \/ 93 | 1 I*\/ 3 || | / 1 \/ 93 | 1 I*\/ 3 || | / 1 \/ 93 |
| 3*3 / - + ------ *|- - - -------|| | 3*3 / - + ------ *|- - + -------|| | 3*3 / - + ------ |
\ \/ 2 18 \ 2 2 // \ \/ 2 18 \ 2 2 // \ \/ 2 18 /