一道SAT数学题12^10 ,12^10＊12^10,12^10＊12^10＊12^10,……In the sequence above,the first term is 12^10and each term after the first is 12^10 more than the preceding term.Which term in the sequence is equal to12^12?A.The 3rd termB.The 12th termC.The 24th termD.The12
2019-05-23
一道SAT数学题
12^10 ,12^10＊12^10,12^10＊12^10＊12^10,……
In the sequence above,the first term is 12^10and each term after the first is 12^10 more than the preceding term.Which term in the sequence is equal to12^12?
A.The 3rd term
B.The 12th term
C.The 24th term
D.The120th term
E.The 144th term
为什么选E?
优质解答
数列的规律：第一个数是12^10,后一个数比前一个数多12^10.
即,第1个是12^10,第2个是12^10+12^10,第3个是12^10+12^10+12^10,……
那么,第n个就是 n x 12^10
因为 12^12=12^(10+2)
=12^2x12^10
=144x12^10
所以第144个数是12^12,故选E.
数列的规律：第一个数是12^10,后一个数比前一个数多12^10.
即,第1个是12^10,第2个是12^10+12^10,第3个是12^10+12^10+12^10,……
那么,第n个就是 n x 12^10
因为 12^12=12^(10+2)
=12^2x12^10
=144x12^10
所以第144个数是12^12,故选E.