## Basic College Mathematics (9th Edition)

2 * $3^{2}$ * 7
126 Try to divide 126 by the first prime number 2 126 = 63 * 2 Try to divide 63 by the prime number 3 63 = 21 * 3 Try to divide 21 by the prime number 3 21 = 7 * 3 So, 126 = 2 * 3* 3 *7 Because all factors are prime, the prime factorization of 126 is 2 * 3*3*7 = 2 * $3^{2}$ * 7