1. T\u00ednh \u0111\u01a1n \u0111i\u1ec7u c\u1ee7a h\u00e0m s\u1ed1<\/b><\/p>\n

– Cho K l\u00e0 kho\u1ea3ng ho\u1eb7c \u0111o\u1ea1n ho\u1eb7c n\u1eeda kho\u1ea3ng. Gi\u1ea3 s\u1eed h\u00e0m s\u1ed1 y = f(x) x\u00e1c \u0111\u1ecbnh tr\u00ean K. Ta n\u00f3i<\/p>\n

+ H\u00e0m s\u1ed1 \u0111\u1ed3ng bi\u1ebfn (t\u0103ng) tr\u00ean K n\u1ebfu m\u1ecdi c\u1eb7p x_{1<\/sub>,x2<\/sub>\u00a0thu\u1ed9c K m\u00e0 x1<\/sub>\u00a0nh\u1ecf h\u01a1n x2<\/sub>\u00a0th\u00ec f(x1<\/sub>) nh\u1ecf h\u01a1n f(x2<\/sub>), t\u1ee9c l\u00e0<\/p>\n}

x_{1<\/sub>\u00a0< x2<\/sub>\u00a0=> f(x1<\/sub>) < f(x2<\/sub>)<\/p>\n}

+ H\u00e0m s\u1ed1 ngh\u1ecbch bi\u1ebfn (gi\u1ea3m) tr\u00ean K n\u1ebfu v\u1edbi m\u1ecdi c\u1eb7p x_{1<\/sub>,x2<\/sub>\u00a0thu\u1ed9c K m\u00e0 x1<\/sub>\u00a0< x2<\/sub>\u00a0th\u00ec f(x1<\/sub>) nh\u1ecf h\u01a1n f(x2<\/sub>), t\u1ee9c l\u00e0<\/p>\n}

x_{1<\/sub>\u00a0< x2<\/sub>\u00a0=> f(x1<\/sub>) > f(x2<\/sub>)<\/p>\n}

– H\u00e0m s\u1ed1 \u0111\u1ed3ng bi\u1ebfn ho\u1eb7c ngh\u1ecbch bi\u1ebfn tr\u00ean K \u0111\u01b0\u1ee3c g\u1ecdi chung l\u00e0 \u0111\u01a1n \u0111i\u1ec7u tr\u00ean K, K \u0111\u01b0\u1ee3c g\u1ecdi chung l\u00e0 kho\u1ea3ng \u0111\u01a1n \u0111i\u1ec7u c\u1ee7a h\u00e0m s\u1ed1.<\/p>\n

Nh\u1eadn x\u00e9t:<\/i><\/b>\u00a0H\u00e0m s\u1ed1 \u0111\u1ed3ng bi\u1ebfn tr\u00ean K th\u00ec \u0111\u1ed3 th\u1ecb h\u00e0m s\u1ed1 \u0111i l\u00ean t\u1eeb tr\u00e1i sang ph\u1ea3i. H\u00e0m s\u1ed1 ngh\u1ecbch bi\u1ebfn tr\u00ean K th\u00ec \u0111\u1ed3 th\u1ecb h\u00e0m s\u1ed1 \u0111i xu\u1ed1ng t\u1eeb tr\u00e1i sang ph\u1ea3i.<\/p>\n

C\u00e2u<\/b>\u00a02. T\u00ednh \u0111\u01a1n \u0111i\u1ec7u v\u00e0 d\u1ea5u c\u1ee7a \u0111\u1ea1o h\u00e0m<\/p>\n

– Gi\u1ea3 s\u1eed h\u00e0m s\u1ed1 y = f(x) c\u00f3 \u0111\u1ea1o h\u00e0m tr\u00ean kho\u1ea3ng (a;b). Khi \u0111\u00f3:<\/p>\n

+ N\u1ebfu f'(x) \u2265 0, \u2200x \u2208 (a; b) v\u00e0 f'(x) = 0 ch\u1ec9 t\u1ea1i m\u1ed9t s\u1ed1 h\u1eefu h\u1ea1n \u0111i\u1ec3m th\u00ec h\u00e0m s\u1ed1 \u0111\u1ed3ng bi\u1ebfn tr\u00ean (a;b).<\/p>\n

+ N\u1ebfu f'(x) \u2264 0, \u2200x \u2208 (a; b) v\u00e0 f'(x) = 0 ch\u1ec9 t\u1ea1i m\u1ed9t s\u1ed1 h\u1eefu h\u1ea1n \u0111i\u1ec3m th\u00ec h\u00e0m s\u1ed1 ngh\u1ecbch bi\u1ebfn tr\u00ean (a;b).<\/p>\n

Ghi ch\u00fa:<\/i><\/b>\u00a0D\u1ea5u b\u1eb1ng x\u1ea3y ra ch\u1ec9 t\u1ea1i m\u1ed9t s\u1ed1 h\u1eefu h\u1ea1n \u0111i\u1ec3m.<\/p>\n","protected":false},"excerpt":{"rendered":"

1. T\u00ednh \u0111\u01a1n \u0111i\u1ec7u c\u1ee7a h\u00e0m s\u1ed1 – Cho K l\u00e0 kho\u1ea3ng ho\u1eb7c \u0111o\u1ea1n ho\u1eb7c n\u1eeda kho\u1ea3ng. Gi\u1ea3 s\u1eed h\u00e0m s\u1ed1 y = f(x) x\u00e1c \u0111\u1ecbnh tr\u00ean K. Ta n\u00f3i + H\u00e0m s\u1ed1 \u0111\u1ed3ng bi\u1ebfn (t\u0103ng) tr\u00ean K n\u1ebfu m\u1ecdi c\u1eb7p x1,x2\u00a0thu\u1ed9c K m\u00e0 x1\u00a0nh\u1ecf h\u01a1n x2\u00a0th\u00ec f(x1) nh\u1ecf h\u01a1n f(x2), t\u1ee9c l\u00e0 x1\u00a0< x2\u00a0=> […]<\/p>\n","protected":false},"author":3,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_mi_skip_tracking":false,"tdm_status":"","tdm_grid_status":""},"categories":[157],"tags":[1447,1446],"yoast_head":"\n