... cn nm c ý nghỡa hỡnh hc ca o hm v ghi nh cỏch vit phng trỡnh tip tuyn ca th hm s TI mt im y = f (x0)(x x0) + f(x0) Về nhà + SGK: cỏc bi 5, 6, (trang 15 6 , 15 7 ), (17 6), (17 7), 20a (18 1) + SBT: ... x0 = hoc x0 )== -1 f '(x 3x TH1: x0 = y0= Tip im l im M0 (1; 1) H s gúc ca tip tuyn k = Vy tip tuyn cú PT y = 3(x - 1) + hay y = 3x - TH2: x0 = -1 y0 = -1 Tip im l im M0( -1; -1) H s gúc ca tip ... x x f (x) f ( 1) x +1 k = f ' (1) = lim = lim = lim (x x + 1) = x Vy tip tuyn cú PT xy+= 4(x x 13 x hay y x 2) + + = 4x Vy tip tuyn cú PT y = 3(x + 1) -1 hay y = 3x + VD5 2) Vit PTTT ca...