问题
解答题
(1)求(log43+log83)(log32+log92)-log
(2)已知a=8,b=-2,求[a-
|
答案
(1)原式=(log223+log233)(log32+log322)-log
21 2 3 4
=(
log23+1 2
log2 3)(log32+1 3
log3 2)+1 2 3 4
=
×5 6
×log23×log32+3 2
=3 4
+5 4
=2.3 4
(2)所化简的式子=[a-
ba-1 2
b-2×(-1 2
) a-1×(-1 2
) ]22 3
=(a-1+
b1+1)2=a-2 3
b4.,2 3
代入a=8,b=-2,
计算得出原式的值为(23)-
×(-2)4=2 3
×16=4.1 4