A math circuit for computing an estimate of a transcendental function is described. A lookup table storage circuit has stored therein several groups of binary values, where each group of values represents a respective coefficient of a first polynomial that estimates the function to a high precision. A computing circuit uses a portion of a binary value, that is also taken from one of the groups of values, to evaluate a second polynomial that estimates the function to a low precision. Other embodiments are also described and claimed.