设a、b满足2a+3b=6,a>0,b>0,则2a+3b的最小值是______.-数学

题目简介

设a、b满足2a+3b=6,a>0,b>0,则2a+3b的最小值是______.-数学

题目详情

设a、b满足2a+3b=6,a>0,b>0,则
2
a
+
3
b
的最小值是
______.
题型:填空题难度:偏易来源:不详

答案

设a>0,b>0,且2a+3b=6,
class="stub"2
a
+class="stub"3
b
=class="stub"1
6
×(class="stub"2
a
+class="stub"3
b
)×(2a+3b)

=class="stub"1
6
×(4+9+class="stub"6b
a
+class="stub"6a
b
)=class="stub"13
6
+class="stub"b
a
+class="stub"a
b

class="stub"13
6
+2
class="stub"a
b
•class="stub"b
a
=class="stub"25
6

当且仅当class="stub"b
a
=class="stub"a
b
a=b=class="stub"6
5
时,取得等号,
class="stub"2
a
+class="stub"3
b
的最小值为class="stub"25
6

故答案为 class="stub"25
6

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