a) A = \(\frac{\sqrt{x+1}}{\sqrt{x-3}}\) Tìm số nguyên x để A có giá trị là 1 số nguyên
b) B= \(\frac{\sqrt{x+1}}{\sqrt{x-1}}\) Chứng minh rằng x= \(\frac{16}{9}\) và x =\(\frac{25}{9}\) Thì B có giá trị bằng 1 số nguyên
c) Cho \(\frac{a}{b}\)=\(\frac{b}{c}\)=\(\frac{c}{d}\) CM (\(\frac{a+b+c}{b+c+d}\))\(^3\) = \(\frac{a}{d}\)
d) Cho \(\frac{a}{b}\)=\(\frac{b}{c}\)=\(\frac{c}{d}\) CM a=b=c
e) Tìm x biết \(\frac{1+2y}{18}\)=\(\frac{1+4y}{24}\)=\(\frac{1+6y}{6x}\)
MỌI NGUỒI LÀM NHANH HỘ EM Ạ
chuyển sang bị động ( dạng đặc biệt lưu ý)
1Her father gave her a beautiful doll on her birthday
2 we gave Ann some bananas and some flowers
3My mother will buy me a new smart phone
4 They sent her beautiful flowers on her birthday
5 My pen friend has written me ten letters
6 we need to water the flowers everyday
7 They suggests planting fruit trees in the garden
Chuyển sang thể bị động
I hate people laughing at me
Her father bought her a doll on her birthday
We gave Ann some bananas and some flowers
They gave her beautiful flowers on her birthday
My mother will buy me a new smart phone
My father waters this flower every morning.