Possible Clues:

• Mathematical ratio cannot get worked out
• Function clear, belt secured
• Function cannot get put off
• One commanding regiment at last, concerned with holding grand function
• *Math reciprocal
• Mathematician's function sends a new fellow to bed
• Can't get on unfortunately with a concept in trigonometry
• Maths function
• In triangular relationship, cannot get out
• Compelling to keep skin colour in proportion