阅读材料:基本不等式eqId412941c4ab2f4c51a6ee5b667f57569feqId161d5eeb687446eeabe9e26dad2f1c44(a>0,b>0),当且仅当a=b时,等号成立.其中我们把eqId161d5eeb687446eeabe9e26dad2f1c44叫做正数a、b的算术平均数,eqId412941c4ab2f4c51a6ee5b667f57569f叫做正数a、b的几何平均数,它是解决最大(小)值问题的有力工具.
例如:在x>0的条件下,当x为何值时,x+eqId5b55a800c13841a9a950777de0f0dec7有最小值,最小值是多少?
解:∵x>0,eqId5b55a800c13841a9a950777de0f0dec7>0∴eqId681b4394da834b8cb64aaa6a00ec8fd8eqIde34793c2805e44ca91532e63a91a837b即是x+eqId5b55a800c13841a9a950777de0f0dec7≥2eqIde34793c2805e44ca91532e63a91a837b
∴x+eqId5b55a800c13841a9a950777de0f0dec7≥2
当且仅当x=eqId5b55a800c13841a9a950777de0f0dec7即x=1时,x+eqId5b55a800c13841a9a950777de0f0dec7有最小值,最小值为2.
请根据阅读材料解答下列问题
(1)若x>0,函数y=2x+eqId5b55a800c13841a9a950777de0f0dec7,当x为何值时,函数有最小值,并求出其最小值.
(2)当x>0时,式子x2+1+eqId43e1445d65d0411faa4901f78c88fd75≥2成立吗?请说明理由.
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