All operations in Solutions are generally binary (that means they must operate on two numbers.) This means the minus sign - may only be used to represent subtraction. It may not be used to represent a negative number. Negative numbers can be constructed by subtracting a larger number from a smaller one (for example: 2-3 expresses negative one).
The times sign must be used for multiplication (implicit multiplication may not be used either with parentheses or by placing a numeral in front of a root sign or variable i.e. 2r9 does not represent two times the square root of nine and 2A cannot represent 2xA without a times sign.)
The small letter r is used for the root symbol. Indexes for root operation are always placed in front of the root sign: 2r9 expresses the square root of nine which equals 3.
The ^ symbol represents exponentiation. The power index for exponentiation comes after the ^ sign and base number: so 3^2 expresses three to the second power which equals 9.
For the logarithm operation, the base number is placed before the L sign and the result comes afterward: 2L8 = Log28 = 3 because 2^3=8.