- If you need clarification, ask it in the comment box above.
- Better answers use proper spelling and grammar.
- Provide details, support with references or personal experience.
Tell us some more! Your answer needs to include more details to help people.You can't post answers that contain an email address.Please enter a valid email address.The email address entered is already associated to an account.Login to postPlease use English characters only.
Tip: The max point reward for answering a question is 15.
To take the log of a number, enter the number then press the LOG button, then the =. To take the log of a negative number, enter the negative number using the +/- key just to the right of the decimal point. To calculate the negative of a log, calculate the log and then negate it using +/-. To calculate the antilog (inverse logarithm), press 2nd then LOG.
Bear in mind that LOG is the common (base-10) logarithm. For the natural (base-e) logarithm, use the LN key to its right.
The inverse of the log function is the power function. For log in base 10 that inverse is 10 to a power of More generally, let b be the base of the logarithm. If y=log_b (x) then x=b^y For your case log=log_10, to calculate the inverse you perform 10^(-2)=0.01=1/100 On calculators the log in base 10 and its inverse share the same physical key. One is accessed directly, the other is the shifted key function.
What you call the antilog is also known as as the power function. More specifically, the inverse of a decimal log is the function 10 to a power, (10^x) It shares the same physical key as the log function. If the calculator has a key marked [LOG] you have to press the [2nd or SHIFT] key followed by the [LOG] key to activate the anti-log.
For natural log (logarithms in base e) the antilog is the exponential function (e^x). It shares the same physical key as the [LN] function.
There are very few instances where you have two press two keys AT THE SAME TIME, the most notable of them is when you want to force the calculator into the BOOT SCREEN. Most key combinations are key sequences, meaning you press a key and THEN press another.
This said, let us get back to your question.
When you apply a function on an expression, then apply the inverse of the function on the result you get the original expression back. If f is a function and f^-1 its inverse, by definition f^-1[f(x)]=f[f^-1(x)] =x As you can see you do not need a calculator to find the result.
Concerning the logarithmic functions
For the natural logarithms (logarithms in base e) labeled [ln], the inverse of the logarithm is the exponential function e^ ln[e^(x)] =e^[ln(x)] =x
For the common logarithms (logarithms in base 10), labeled [log], the inverse function of the log is the raising 10 to the power of. It is usually called the antilogarithm or antilog.
y= log(x) is equivalent to x=10^(y)
Try the following exemple
log(14) = 1.146128036 10^(1.146128036) =14
To access the 10^x function you press [2nd][LOG] To access the exponential function you press [2nd][LN]