✔ 最佳答案
1)
√484
= √ (2 x 2 x 11 x 11)
= (√2 x √2) x (√11 √ 11)
= 2 x 11
= 22
2)
√576
= √ [(2^6) x 3 x 3]
= (√2^6) x ( √3 x √3)
= 2^3 x 3
= 8 x 3
= 24
3)
√729
= √ (3^6)
= 3^3
= 27
4)
√1225
= √ (5 x 5 x 7 x 7)
= (√ 5 x √5) x (√7 x √7)
= 5 x 7
= 35
要先質因數分解,如 √484 = √ (2 x 2 x 11 x 11),然後要是有 2 個一樣的 質因數,便抄 1 個 下來,再把平方根號刪除,如 √ (2 x 2 x 11 x 11) = 2 x 11,但如果多了 1 個質因數出來,便將它寫在平方根號里,如
√45
= √ (3 x 3 x 5)
= 3 x √5
= 3√5
2007-08-09 09:05:14 補充:
√484 -----------------質因數分解= √ (2 x 2 x 11 x 11)= √ (2 x 2) x √ (11 x 11)= 2 x 11= 22Is that OK ?