1.Область определения функции: x∈R (функция определена на x∈(-∞;+∞).2.Четность/нечетность: f(-x)=-(-x)³+3(-x)²-4=x³+3x²-4≠f(x)≠-f(x) - функция ни четная, ни нечетная.3.Непрерывность: функция непрерывна на всей области определения.4.Поведение функции при x→+-∞: при x→-∞, f(x)→+∞; при x→+∞, f(x)→-∞.5.Производная функции: f'(x)=(-x³+3x²-4)'=-(x³)'+3*(x²)'-4'=-3x²+3*2x-0=-3x²+6x.6. Экстремумы функции: f'(x)=0, -3x²+6x=0 ⇒ x²-2x=0 ⇒ x(x-2)=0 ⇒ x=0 и x=2.7.Монотонность (промежутки возрастания и убывания) функции: при x∈(-∞;0], f'(x)<0 - функция убывает, при x∈[0;2], f'(x)>0 - функция возрастает, при x∈[2;+∞), f'(x)<0 - функция убывает. Следовательно x=0 - точка минимума, x=2 - точка максимума.8.Пересечение графика функции с осями координат: с осью абсцисс, f(x)=0 ⇒ -x³+3x²-4=0 ⇒ x=-1 и x=2, получим точки (-1;0) и (2;0); с осью ординат, x=0, f(x)=-4, получим точку (0;-4). Подробнее - на -
1 yesterday i had breakfast at the canteen. 2 last summer we went to the black sea. 3 he didn't call me last week. 4 why did this girl come to our office yesterday? 5 when did you buy tickets last time? 6 last june the boys played football every morning. 7 on sunday my parents were at the theatre. 8 i didn't take part at the conference last month. 9 he lived in kiev in his childhood. 10 where did he send his message? 2 трансформируйте предложения в past simplе 1 he often played chess. 2 our classes began at 9 a. m. 3 she was always busy. 4 what did you do in the evening? 5 my sister didn’t study at school, she worked at the hospital. 6 my friend prefered tea to coffee. 7 i found many stories in this magazine. 8 he was in my room, wasn't he? 9 why did you always ask so many questions? 10 jasmine seldom visited her grandparents. 3 образуйте отрицательную форму предложений 1 in summer she didn't get up early. 2 mr. white didn't write a lot of letters yesterday. 3 on friday they weren't at the station. 4 we didn't enjoy our time in rome. 5 they didn't watch a football match last weekend. 6 the girl didn't open a box at once. 7 i didn't leave my keys on the table. 8 the engineer didn't go on business trip on monday. 9 my friend didn't want to move to another flat. 10 i didn't find a surprise in the present-box. 4 поставьте вопросы к предложениям. 1 he learned english at school. (where? what language? why? or …? ) where did he learn english? what language did he learn? why did he learn english? did he learn english or french? 2 the train was five hours late. (what? why? ) what was 5 hours late? why was the train five hours late? 3 i was going to stay at my aunt’s in the crimea. (where? who? or …? ) where was i going to stay in the crimea? who was going to stay at the aunt's in the crimea? was i going to stay at my aunt's or in the hotel in the crimea? 4 they stayed in moscow only for two days. (why? where? how long? ) why did they stay in m only for 2 days? where did they stay? how long did they stay in m? 5 i bought a very beautiful dress in this shop last weekend. (where? what? when? ) where did i buy a very beautiful dress last weekend? what did i buy in this shop last weekend? when did i buy this beautiful dress in the shop? 6 they traveled to cyprus by sea. (how? where? or …? ) how did they travel to c? where did they travel to? did they travel to c or ibiza? 7 i didn’t find your telephone number. (what? why? ) what didn't i find? why didn't i find your telephone number? 8 in his childhood he was always a leader among his friends. (what? when? who? ) what was he in his childhood? when was he a leader among his friends? who was always a leader among his friends in his childhood? 9 he caught a cold last month. (what? when? why? ) what did he catch? when did he catch a cold? why did he catch a cold? 10 we did our lessons together. (what? how? ) what did we do together? how did we do our lessons?
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