已知a^2-5a+2=0,求2a^4-10a^3+7a^2-15a+2016的值
问题描述:
已知a^2-5a+2=0,求2a^4-10a^3+7a^2-15a+2016的值
答
因为a²-5a+2=0,所以:
2a^4-10a^3+7a^2-15a+2016
=2a^4-10a^3+4a²+3a^2-15a+6+2010
=2a²(a²-5a+2)+3(a²-5a+2)+2010
=2010