\(81^7-27^9-9^{13}=3^{4.7}-3^{3.9}-3^{2.13}=3^{28}-3^{37}-3^{26}\)

\(=3^{26}\left(9-3-1\right)=5.3^{26}\)mà 3²⁶ chia hết cho 9, do đó \(5.3^{26}\)chia hết cho 45

chia hết cho j bn?

Cảm ơn bạn mình giải được rồi

14-14=16-16(=0)

7(2-2)=8(2-2)

7=8

\(7=8\)

\(7=7+1\)

\(7=7+\left(0,5+0,5\right)\)

\(7=7+\left(0,5+\sqrt{0,25}\right)\)

\(7=7+\left(0,5+-0,5\right)\)

\(7=7+\left(0,5-0,5\right)\)

\(7=7+0\)

\(7=7\)

Từ \(7=8\)ra \(7=7\), ta có thể sử dụng căn bậc hai để biến đổi hoàn toàn biểu thức so sánh . Nếu số to quá mà đưa về căn bậc hai thì có thể để ở dạng \(\sqrt{x^2}\).

Hoàn toàn có thể CMR 7 = 8

được k khi trả lời đúng nha

càng nhìu càng tốt

ok?

Trả lời các câu hỏi của người khác rồi họ bấm đúng sẽ dc diểm hỏi đáp

2x+3 chia hết cho x

Mà 2x chia hết cho x =>3 chia hết cho x=> x thuộc ước của 3

=> x thuộc (-1;1;-3;3)

a,4a12b chia hết cho 2,5,9 là:42120

b,5a43b chia hết cho 2,5,9 là56430

c,40ab chia hết cho 2,3,5 là: 4020

K CHO MIK NHA

Citrullus lanatus is a species of plant in the Cucurbitaceae family, a vine- flowering plant native to West Africa. It is grown for fruit. This melon divides into two varieties, watermelon (watermelon (Thunb.) Var. Lanatus) and Citrullus caffer (watermelon var. Citroides (LH Bailey) Mansf.) Derived from the misnaming of Citrullus lanatus (Thunb .) Matsum. & Nakai and Citrullus Vulgaris Schrad. by LH Bailey in 1930. [1] Molecular data includes strings from Thunberg's original collection and other related materials, showing sweet watermelon (Citrullus Vulgaris Schrad.) And bitter melon Citrullus lanatus (Thunb.) Matsum. & Nakai are not closely related. [2] Since 1930, thousands of newspapers have misused the name Citrullus lanatus (Thunb.) Matsum. & Nakai for watermelon, and a proposal to preserve a name in this sense was accepted by the relevant nomenclature committee and confirmed at the International Botanic Congress in Shenzhen. [3]

The first South African bitter melon collected by Thunberg was imported into semi-deserts on several continents, and was designated a "pest tree" in regions of Western Australia where they are called melons. pig. [4]

Watermelon (Citrullus lanatus) is a long, twisted vine in the Cucurbitaceae family of flowering plants. This species is thought to have originated in southern Africa, but this is based on the erroneous LH Bailey (1930) identity of a watermelon grown in South Africa. [5] The error became apparent when comparing DNA of a watermelon grown and named Linnaeus and South African cultivars. [6] There is evidence from watermelon seeds in Pharaoh's tombs in ancient Egypt. Watermelon, grown in tropical and subtropical regions around the world for its fruit, is a special type of berry with a hard shell and no cleavage in the fruit, botanical called pepo. . The flesh is sweet, succulent, usually dark red to pink, with many black seeds, although seedless varieties have also been produced. The fruit can be eaten raw or processed, and the skin can be eaten after cooking.

Crossing efforts have produced disease-resistant varieties of watermelon. Many varieties of watermelon can bear fruit to maturity within 100 days of sowing.