35 TRUNG TÂM D Y THÊM Câu LÊ H NG PHONG = (C) : D = R\{ 1} : y=2 a * * lim (C) , lim ; lim * y' = ( * y' > 0, * x y' 0.25 x= 0.25 ) x D : + * ; 0); ( 2; 5); ( : (0; 1); ( ; ) : -5 -4 -3 -2 -1 -1 -2 b y 0.5 x (C) (d) 0.25 + y * ( 1; 4) 0.75 (C) (x0; y0) (d): y y0 = y'(x0)(x x0) (d): y = ( ) (d) qua A + 2x0 ( ( ) ( ) = 4x0 + (d): y = ( 0.25 2x0 = ) = : I= ( ) I= x0 = ( )= y0 = 3; y'( 4) = 0.25 1.0 0.25 * I1 = * I2 = 0.25 ) =e 0.25 : u=x v' = ex, u' = ex = ex 0.25 36 TRUNG TÂM D Y THÊM LÊ H NG PHONG I2 = = = =e + = e : 3sinx + cos2x = (1) 2sin x + 3sinx = 2sin2x 3sinx + = a sinx = 0.25 0.5 0.25 = * sinx = 0.25 sin * sinx = b log : log log 0.5 (2) = log3x (x > 0) (1) 0.25 : log3x t 2 x 0.25 , >0 a 0.5 , ( ) ! : !( ( ) ! )! ( )! ! !( n + = 15 n = 11 = = )! 0.25 ( ) k = khai tri 0.25 ( ) b , ng A 0.5 , = 70 " C " = 30 37 : 0.25 38 TRUNG TÂM D Y THÊM LÊ H NG PHONG = (A; B) (A2 + B2 > 0) CD: A(x + 3) + B(y + 3) = Ax + By + 3A + 3B = A B M 0.25 D C : SBCD = SACD = 18 d(A; CD) = d(M; CD) = 0.25 25(36A2 + 48AB + 16B 2) = 90(A2 + B2) 810A2 + 1200AB + 310B = * : = A=1 (CD): x : CD2 = 90 (3d + 9)2 + (d + 3) = 90 D(6; 0) ( ) hay D( 12; 6) ( ) ( * : ; ) 3y = D(3d + 6; d) (d + 3)2 = d = hay d = (6; 0) A(0; 2) 0.25 B( 3; 1) = 27 ; A = 31 ( CD: 31x 27y + 12 = ( ) ) ( 0.25 ) B( 3; 1) () : : (1) ( x ) 0.25 : (2) (3) = : (3) Khi x = * 1.0 ( ) 2t = t ( ) ( ) 0.25 ( y= x=2 y = y=0 ; , 0.25 ) = ; 39 = 2, y = 0.25 TRUNG TÂM D Y THÊM LÊ H NG PHONG Cho x, P= ( * ( * = (12 + 12)(x2 + y2) 3 1.0 ) ( ) (x + y)2 2(x + y ) : ) ( , + y2 = 2 = x3 + y3 x+y (x + y)(x + y ) ) 0.25 x +y ; : = (x2 + y2)3 = x6 + y6 + 3x2y2(x2 + y2) = x6 + y6 + 6x2y2 = (x3 + y3)2 2x3y3 + 6x2y2 2x3y3 6x2y2 = t2 * 2(x3 + y3) = (x3 + y3)(x2 + y2) = x5 + y5 + x2y3 + x3y2 = x5 + y5 + x2y2(x + y) x5 + y5 + x2y2(x + y) = 2t *2 P = ( = = = 0.25 ) 4x3y3 + 12x2y2 + 5(x5 + y5) + 5x2y2 3 2 5 0.25 2 2(2x y 6x y )+ 5(x + y ) + 5x y 2(t2 8) + 5[x5 + y5 + x2y2(x + y)] = f '(t) = 4t + 10; f '(t) = t= ; 2t2 + 10t + 16 = f(t) : f(2) = 28; () ( ) 0.25 () ; ; 40