二次函数的最值问题hhhhhhhhhhhhhh

1234kx1x2x1x2kx1kx2af(k)k1x1x2k2x1x2k1x1x2k2f(k1)f(k2)0f(k1)=0f(k2)=0k1x1k2p1x2p251xy0aOabx2-=pqf(p)f(q)xy0aOabx2-=pqf(p)f(q)xy0aOabx2-=pqf(p)f(q)xy0aOabx2-=pqf(p)f(q)xy0aOabx2-=pqf(p)f(q)()(1xy0aOabx2-=pqf(p)f(q)xy0aOabx2-=pqf(p)f(q)xy0aOabx2-=pqf(p)f(q)0ayxy0aOabx2-=pqf(p)f(q)f(q)pqOxf(p)12341123421233452121.1a232m()11y(0,11)ABCD2x=1c=_______21()ABCD2xABCD3abc_________xyO31aABCD2(,1)_______341[0,m]32mABCD2MmM+m________3[0,2]3a5R1A.B.C.D.2________3(I)(II)6(1)(2)(3)12x=1[a________34c=0b=0c00c7(1)(2)1A.B.C.D2y=cos2x+sinx__________81f(x)=lg(ax2+2x+1)(I)f(x)Ra(II)f(x)Ra2123123