A B C

Đường trung trực của một đoạn thẳng là đường vuông góc với đoạn thẳng tại trung điểm của đoạn thẳng đó.

Giúp đi ạ 

Xin mn đó

Làm ơn đi

Ai trả lời nhanh nhất tui k cho

N = (-y² + 4)(2y³ + 6y - 1) + 2(y⁵ - 4y³ + 2)-  y²(-6y + 1)

N = -y²(2y³ + 6y - 1) + 4(2y³ + 6y - 1) + 2y⁵ - 8y³ - 4 + 6y³ - y²

N = -2y⁵ - 6y³ + y² + 8y³ + 24y - 4 + 2y⁵ - 8y³ - 4 + 6y³ - y²

N = (-2y⁵ + 2y⁵) + (-6y³ + 8y³ - 8y³ + 6y³) + (y² - y²) + 24y + (-4 - 4)

N = 24y - 8

Thay y = -3,5 vào biểu thức N ta có :

N = 24.(-3,5) - 8 = -84 - 8 = -92

Ta có : \(x^2+x+4=x^2+x+\frac{1}{4}+\frac{15}{4}=\left(x+\frac{1}{2}\right)^2+\frac{15}{4}>0\left(\forall x\right)\)

+) \(\left(x-1\right)\left(x^2+x+4\right)=0\)

\(\Leftrightarrow x-1=0\Leftrightarrow x=1\)

\(\left(x-1\right)\left(x^2+x+4\right)=0\)

\(\Leftrightarrow\orbr{\begin{cases}x-1=0\\x^2+x+4=0\end{cases}}\Leftrightarrow\orbr{\begin{cases}x=1\\x^2+x=-4\end{cases}}\)

+) x² + x = - 4

<=> ( x + 1/2 )² = - 4 + 1/4 = -15/4

Mà ( x + 1/2 )² lớn hơn hoặc bằng 0 với mọi x

=> x² + x + 4 = 0 ktm

Vậy pt = 0 <=> x = 1

101x789+456x128+789-921x463=

-287577

128504

thi kiểu gì

Không đăng linh tinh nha bạn.

thiếu đề bẹn ẹ

a) E= 

X³- 3.5x² + 3.5²x + 5³

X³- 3.5x² + 3.5²x + 5³

(a + 5)³

b) = X² – xy + x² + xy

= 2x²

b) Tại x=14 thì:\(B\left(x\right)=x^5-15x^4+16x^3-29x^2+13x\)

\(=x^5-\left(x+1\right)x^4+\left(x+2\right)x^3-\left(2x+1\right)x^2+x\left(x-1\right)\)

\(=x^5-x^5-x^4+x^4+2x^3-2x^3-x^2+x^2-x=-x=-14\)

a) A(x)=1

cậu giúp mình nốt phần kia đc k cậu

\(\frac{-1}{6}.\frac{-15}{19}.\frac{38}{45}=\frac{1}{9}\)

\(\frac{1}{9}\)

* Bạn tham khảo 

The summer holidays are the best time to relax and enjoy with family and friends, this is a time I have always been looking forward to waiting for every year. These summer vacations are very special for me as it is my first time spending time with my colleagues. We had a good time in Vung Tau - the city with the best beaches in Vietnam. We stayed for 2 days in a small but convenient motel. The first day, we got up early to watch the sunrise on the beach. It was the brightest thing I have ever seen. After that, we swam and lay on the sand enjoying the beautiful sun and clear blue skies. We also tasted delicious seafood and fresh coconut water. Next day we took about 30 minutes to walk to Little Mountain to visit the lighthouse. But it really doesn't work! The lighthouse offers a panoramic view of Vung Tau city and is a really interesting place. On top of a small mountain, there is a huge statue of Jesus, 28 meters high, overlooking the South China Sea. This is the largest sculpture of South Vietnam. The statue's shoulder is also a series of balconies, each of which can accommodate up to six people, offering stunning views of the surrounding landscape. The weather during our stay was very nice and the locals were very friendly. We have taken a lot of photos to preserve this memorable vacation and we also bought a lot of souvenirs. I have a lot of good memories of the whole trip. All good, but what makes the trip even more wonderful is the fact that I have built stronger relationships with my colleagues.