已知:a>0,b>0.求证:(a+b)(a^4+b^4)< =2(a^5+b^5)

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已知:a>0,b>0.求证:(a+b)(a^4+b^4)< =2(a^5+b^5)
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已知:a>0,b>0.求证:(a+b)(a^4+b^4)< =2(a^5+b^5)
已知:a>0,b>0.求证:(a+b)(a^4+b^4)< =2(a^5+b^5)

已知:a>0,b>0.求证:(a+b)(a^4+b^4)< =2(a^5+b^5)
2(a^5+b^5)-(a+b)(a^4+b^4)
=a^5+b^5-b*a^4-a*b^4
=a^4*(a-b)+b^4*(b-a)
=(a^4-b^4)(a-b)
=(a+b)(a-b)^2(a^2+b^2)
因为a>0;b>0,
所以(a+b)(a-b)^2(a^2+b^2)>=0
即证