# bc > An arbitrary precision calculator language. > More information: . - Start `bc` in interactive mode using the standard math library: `bc -l` - Calculate the result of an expression: `bc <<< "(1 + 2) * 2 ^ 2"` - Calculate the result of an expression and force the number of decimal places to 10: `bc <<< "scale=10; 5 / 3"` - Calculate the result of an expression with sine and cosine using `mathlib`: `bc -l <<< "s(1) + c(1)"`