If you're talking about QuickBasic 4.5 for DOS it does. Only Ln but that is enough
LOG function
■ Action
Returns the natural logarithm of a numeric expression
■ Syntax
LOG(n)
■ Remarks
The numeric expression, n, must be greater than zero. The natural
logarithm is the logarithm to the base e. The constant e is approximately
equal to 2.718282.
The LOG function calculates the natural logarithm with single-precision
accuracy, unless the argument n is a double-precision value. In this case
LOG is calculated with double-precision accuracy.
You may calculate base-10 logarithms by dividing the natural logarithm of
the number by the logarithm of 10. The following FUNCTION calculates
base-10 logarithms:
FUNCTION Log10(X) STATIC
Log10=LOG(X)/LOG(10.#)
END FUNCTION
■ Example
The following example first prints the value of e and then prints the
natural logarithms of e taken to the first, second, and third powers:
PRINT EXP(1),
FOR I = 1 TO 3
PRINT LOG(EXP(1)^I),
NEXT
■ Output
2.718282 1 2 3