30. TIPS WHEN YOU USE A FORMULA

When you want to use some formula, write down it, and confirm it in short time. Is it correct? Do I make a mistake like “+” instead of “-” ? This case is often. To confirm formulas, input simple values. For example, following formula

　　　sin(A+B)=sinA cosB + cosA sinB.
To confirm this, input A=pi/3, B=pi/6. If you put “-” instead of correct “+”, you get wrong value.
After confirming formulas, you can use these at ease.

See you next.

Nasuno Kumao