问题
解答题
计算下列各式 (Ⅰ)(lg2)2+lg5•lg20-1 (Ⅱ)(
|
答案
(Ⅰ)原式=lg22+(1-lg2)(1+lg2)-1=lg22+1-lg22-1=0
(Ⅱ)原式=(2
×31 3
)6+(21 2
) 3 4
-14 3
=22×33+2-1=109.
计算下列各式 (Ⅰ)(lg2)2+lg5•lg20-1 (Ⅱ)(
|
(Ⅰ)原式=lg22+(1-lg2)(1+lg2)-1=lg22+1-lg22-1=0
(Ⅱ)原式=(2
×31 3
)6+(21 2
) 3 4
-14 3
=22×33+2-1=109.