用导数证明不等式是证不等式的一种重要方法,证明过程往往简捷、明快,特别是证明超越不等式,更是如鱼得水.证明的第一步要考虑如何构造函数,是证明的关键.若函数构造恰当,把不等式的证明转化为利用导数研究函数的单调性或求最值,从而证得不等式.本文谈谈在用导数证明不等式时,? Using derivatives to prove inequalities is an important way to prove inequalities, proving that the process is often simple and crisp, especially beyond the inequality of proves that it is like a duck in water. The first step to prove is how to construct a function, which is the proof of key. If the function is properly constructed , The proof of inequality is transformed into the monotonicity or the supreme value of the function by using the derivative, so as to prove the inequality.