Coi 2 cạnh của hình chữ nhật là a và b, a+b=10.Sử dụng BĐT Cauchy: \(ab\le\frac{a^2+b^2}{2}\)Dấu "=" xảy ra khi a=b=5 tức là max(ab)=25
Đúng 0
Bình luận (0)
Violympic toán 8
Các câu hỏi tương tự
Let the rectangle ABCD, AB=2/3BC and the area is 24cm2. What is the perimeter of the rectangle ABCD
Toán tiếng anh: A rectangle has length pcm and width qcm, where p and q are integer. If p and q satisfy the equation pq+q=13+q2 then the maximum possible area of the rectangle is.........
The diagarm shows a rectangle PQRS and T is a point on PS such that QT is perpendicular to RT. The length of QT is 4cm. The length of RT is 2cm. What is the area of the rectangle PQRS?
a rectangle has length p and breadth p where p,q are intergers . If p, q satisfy the equation pq+q=13+q^2. What is the maximun of the area of the rectangle?
Given that ABCD is a rectangle with AB = 12 cm, AD = 6 cm. M and N are respectively midpoint of segments BC and CD. Find the area of triangle AMN in square centimeters.
Half of the perimeter of a rectangular school yard is 0.24km. The width is of the length. Find the area of the yard in square meters?
Giai bang TA ho minh nhe
alculate: Câu 2:If you walk 45 minutes at a rate 4km/h and then run for 30 minutes at a rate of 10km/h, how many kilometers will you have gone at the end of one hour and 15 minutes?Answer: km. Câu 3:What is the maximum possible area, in , of a rectangle with a perimeter of 20cm?Answer: . Câu 4:Fill the missing number in the blank: Câu 5:In a magic triangle, each of the six whole numbers 10; 11; 12; 13; 14; 15 is placed in one of the circles so that the sum, S, of the three numbers on each side...
Đọc tiếp
alculate:
(1-\frac{1}{3})(1-\frac{1}{4})\ldots(1-\frac{1}{10})(1-\frac{1}{11})]=$)
Câu 2:
If you walk 45 minutes at a rate 4km/h and then run for 30 minutes at a rate of 10km/h, how many kilometers will you have gone at the end of one hour and 15 minutes?
Answer: km. Câu 3:
What is the maximum possible area, in
, of a rectangle with a perimeter of 20cm?
Answer:. Câu 4:
Fill the missing number in the blank:
(3x+10)$)
Câu 5:
In a magic triangle, each of the six whole numbers 10; 11; 12; 13; 14; 15 is placed in one of the circles so that the sum, S, of the three numbers on each side of the triangle is the same. The largest possible value for S is Câu 6:
Find the highest common factor of 147x and 98y if HCF(x;y)=1.
Answer: Câu 7:
Let(x+b)$)
. Find the value of 
.
Answer:
Câu 8:
In triangle ABC, the measure of angle B is
less than 1.5 times the measure of angle A and the measure of angle C is less than 2.5 times the measure of angle A. What is the measure of angle A in degrees?
Answer: The measure of angle A is
. Câu 9:
Write the next number in the sequence: 8; 24; 72; Câu 10:
Complete:
^2$)
Giúp mik với, có lời giải chi tiết nha. Thanks cả nhà =))))
If you walk 45 minutes at a rate 4km/h and then run for 30 minutes at a rate of 10km/h, how many kilometers will you have gone at the end of one hour and 15 minutes?
Answer: km. Câu 3:
What is the maximum possible area, in
Answer:
Fill the missing number in the blank:
In a magic triangle, each of the six whole numbers 10; 11; 12; 13; 14; 15 is placed in one of the circles so that the sum, S, of the three numbers on each side of the triangle is the same. The largest possible value for S is Câu 6:
Find the highest common factor of 147x and 98y if HCF(x;y)=1.
Answer: Câu 7:
Let
Answer:
In triangle ABC, the measure of angle B is
Answer: The measure of angle A is
Write the next number in the sequence: 8; 24; 72; Câu 10:
Complete:
A rectangular garden has length of x ( dm ) and area of 252 dm2. If the width is 5 dm less than one - third of the length, then the perimeter of this garden is ... dm
A rectangle has a length of 60cm and a width of 30cm. It is cut into 2 indentical squares, 2 identical rectangles and a shaded small square. Find the area of the shaded square.
Find the area of the shaded square.
