Question

已知实数a,b满足√4a-b+11+√1/3b-4a-3=0 求(√b/a÷√1/b)·2a√a/b的值

答案是√3

步骤清楚

满意加分

Answer 1

√(4a-b+11)+√(1/3b-4a-3)=0
4a-b+11=0................1
1/3b-4a-3=0
b-12a-9=0
12a-b+9=0 .............2
2式-1式得
8a-2=0
a=1/4
b=12

[√(b/a)]÷√(1/b)*2a√(a/b)
=[√(b/a)*√b]*2a√(a/b)
=[√(b/a)*√(a/b]*2a*√b
=2a*√b
=2*1/4*√12
=2*1/4*2√3
=√3
=(√b/a*√b)*2a√(a/b)

Answer 2

4a-b+11=0
1/3b-4a-3=0
a=-3,b=-1
(√b/a÷√1/b)·2a√a/b=b/√a*2a√a/b=√(ab)=√3