a,  đặt t = căn x suy ra t lớn hơn bằng 0

quy đồng  nhân từ  (t-1) ( t+3) ta đc P =    ((t^2 +16 ))/ t +3 

các câu sau tự làm nha

what is her mother going to prepare for her bỉthdat party

there are three sticks of butter in the cupboard

i have enough food for the first three day of your stay

\(a,\dfrac{1}{2}x=3+2\)

\(\dfrac{1}{2}x=5\)

\(x=5\div\dfrac{1}{2}\)

\(x=10\)

\(b,\dfrac{1}{4}x^2-\sqrt{36}=10\)

\(\dfrac{1}{4}x^2-6=10\)

\(\dfrac{1}{4}x^2=10+6\)

\(\dfrac{1}{4}x^2=16\)

\(x^2=16\div\dfrac{1}{4}\)

\(x^2=64\)

\(x^2=\left(8\right)^2\)

\(\Rightarrow x=8\)

sai đề k

1. The police pointed a finger at the man of stealing the car.

2. Mary has a good head on her shoulders.

3. My lawyer now has the matter on his hands.

[cos (3x + π/2) + 1] . sin (x + π/5) = 0 (*)

<=> cos (3x + π/2) + 1 = 0 hoặc sin (x + π/5) = 0

<=> cos (3x + π/2) = -1 hoặc sin (x + π/5) = 0

<=> 3x + π/2 = π + k2 π hoặc x + π/5 = k π (k∈Z)

<=> x = π/6 + k2 π/3 hoặc x = - π/5 + k π (k∈Z)

Vậy phương trình (*) có các họ nghiệm …

Cao nhân xin chịu thua.

:))

Áp dụng hệ thức (1) ta có

\(AC^2=AK.AB\Rightarrow AK=\frac{AC^2}{AB}=\frac{12^2}{15}=9,6\)

\(BK=15-AK=15-9,6=5,4\)

Áp dụng hệ thức (2)

\(CK^2=AK.BK=9,6.5,4=51,84\Rightarrow CK=7,2\)

Áp dụng pytago ta có

\(AB^2=AC^2+BC^2\Rightarrow AB=\sqrt{AC^2+BC^2}=\sqrt{12^2+9^2}=15\)

`x xx 2/7=7/5`

`=> x= 7/5 : 2/7`

`=> x= 7/5 xx 7/2`

`=>x= 49/10`