(1)计算:(27/9) 1/2+(lg5)0+(27/64) −1/3; (2)解方程:log3(6x-9)=3.
问题描述:
(1)计算:(2
) 7 9
+(lg5)0+(1 2
) −27 64
;1 3
(2)解方程:log3(6x-9)=3.
答
(1)(2
)7 9
+(lg5)0+(1 2
)−27 64
1 3
=(
) 25 9
+(lg5)0+[(1 2
)3] −3 4
1 3
=
+1+5 3
=4.4 3
(2)由方程log3(6x-9)=3得
6x-9=33=27,
∴6x=36=62,∴x=2.
经检验,x=2是原方程的解.
∴原方程的解为x=2.