Question

（1）化简与求值：(0.0081)-

1

4

-[3(

7

8

)0]-1•[81-0.25+(

27

8

)-

1

3

]-

1

2

-10×0.027

1

3

；
（2）化简与求值：log2

7 48

+log212-

1

2

log242-1．

Answer 1

（1）(0.0081)-

1

4

-[3(

7

8

)0]-1•[81-0.25+(

27

8

)-

1

3

]-

1

2

-10×0.027

1

3

=[(0.3)4]-

1

4

-3-1•[(34)-

1

4

+(

3

2

)-1]-

1

2

-10×(0．33)

1

3

=

10

3

-

1

3

×(

1

3

+

2

3

)-

1

2

-3
=

10

3

-

1

3

-3=0；
（2）log2

7 48

+log212-

1

2

log242-1
=

1

2

log2

7

48

+log212-

1

2

log242-1
=

1

2

(log2

7

48

-log242)+log212-1
=

1

2

log2

1

288

+log212-1
=-

1

2

log22×122+log212-1
=-

1

2

(1+2log212)+log212-1
=-

1

2

-1=-

3

2

．