曲線y=x3-2x2-4x+2在點(1,-3)處的切線方程是() A. 5x+y+2=0B. 5x+y-2=0C. 5x-y-8=0D. 5x-y+8=0

曲線y=x3-2x2-4x+2在點(1,-3)處的切線方程是() A. 5x+y+2=0B. 5x+y-2=0C. 5x-y-8=0D. 5x-y+8=0

∵曲線y=x3-2x2-4x+2,∴y′=3x2-4x-4,當x=1時,y′=-5,即切線斜率為-5,∴切線方程為y+3=-5(x-1),即5x+y-2=0.故選B.