Choose the best answer to complete the following sentences

1. Doctor said that if he practiced ............ every day, he could keep his mind stress- free .

A. immune system. B.meditation. C.acupuncture

D. a diet

2. Sleep,rest and relaxation can slow down the.........

A. ageing process

B. life expectancy

C. cholesterol

D. health

3. The boy ........ to me for breaking my flower vase.

A . advised

B. suggested

C. apologized

D. accused

4. If you catch a cold, you should try natural........ before taking any medicine.

A. medicines

B. remedies

C.foods

D. ways

5. Fas food .....can increase the risk of obesity and heart disease.

A. consumptions

B. consuming

C.consume

D.consumption

6. Staying .......is half of the secret to weight control ,the other half is healthy diet.

A. active

B.actively

C.inactive

D.inactively

7. Mantine hasn't quite ..... his illness yet

A. recovered

B. got over

C.looked after

D. suffered

8.After spending a week in bed,she made a complete.......

A. recover

B.recovering

C.recovery

D.recovered

9.If you...... the doctor's advice,you won't get well.

A.take

B.follow

C.ignore

D.don't listen

10. Daily exercise and weight control strongly influence your chances of staying.......

A. health

B.healthy

C.healthily

D.active

Cho hình chóp tứ giác đều S.ABCD , cạnh đáy bằng a , cạnh bên bằng \(\frac{a\sqrt{5}}{2}\). Gọi O là tâm của hình vuông ABCD và M là trung điểm của SC.

a) Chúng minh rằng : (MBD) vuông góc với (ABCD)

b) Tính góc giữa hai mặt phẳng (MBD) và (ABCD)

c) Tính góc giữa hai mặt phẳng (SAB) và (ABCD)

Giải phương trình f'(x) = g(x) với

a) \(\left\{{}\begin{matrix}f\left(x\right)=sin^43x\\g\left(x\right)=sin6x\end{matrix}\right.\)

b) \(\left\{{}\begin{matrix}f\left(x\right)=sin^32x\\g\left(x\right)=4cos2x-5sin4x\end{matrix}\right.\)

c) \(\left\{{}\begin{matrix}f\left(x\right)=2x^2cos^2\frac{x}{2}\\g\left(x\right)=x-x^2sinx\end{matrix}\right.\)

d) \(\left\{{}\begin{matrix}f\left(x\right)=4xcos^2\frac{x}{2}\\g\left(x\right)=8cos\frac{x}{2}-3-2sinx\end{matrix}\right.\)

Giải phương trình f'(x) =0 với :

a) f(x)= sin²x + 2cosx

b) f(x) = sinx - \(\frac{cos4x}{4}\)-\(\frac{cos6x}{6}\)