Question: what is the square root of 18 in radical form?
Answer: Actually, it is a recurring decimal, so to be accurate, and also for convenience, we express part of the square root as a whole number and another part as a surd. 18 = 2×9, so √18= √(2×9). That makes it easier because 9 is a squàre of 3 and the whole thing now can be expressed as 3√2. The “√2” is the surd.