Register Now

Login

Lost Password

Lost your password? Please enter your email address. You will receive a link and will create a new password via email.

222-9+11+12:2*14+14 = ? ( )

Toán Lớp 7: $\dfrac{a}{b}$= $\dfrac{c}{d}$ $\ne$ 1 thì $\dfrac{a+b}{a-b}$ = $\dfrac{c+d}{c-d}$ với a,b,c $\ne$ 0

Toán Lớp 7: $\dfrac{a}{b}$= $\dfrac{c}{d}$ $\ne$ 1 thì $\dfrac{a+b}{a-b}$ = $\dfrac{c+d}{c-d}$ với a,b,c $\ne$ 0

Comments ( 2 )

  1. Giải đáp:
    Lời giải và giải thích chi tiết:
    a/b=c/d
    a/b=c/d=> a/c=b/d=(a+b)/(c+d)
    a/b=c/d=> a/c=b/d=(a-b)/(c-d)
    (a+b)/(c+d)=a/b=c/d= (a-b)/(c-d)
    =>(a+b)/(c+d) = (a-b)/(c-d) 
    => (a+b)/(a-b)=(c+d)/(c-d)
    Nếu sai cho mik xl ạ

  2. Giải đáp:
    Ta có: $\dfrac{a}{b} = \dfrac{c}{d}$
    $\to 1 + \dfrac{a}{b} = 1 + \dfrac{c}{d}$
    $\to \dfrac{a + b}{b} = \dfrac{c + d}{d}$
    -> {a + b}/{c + d} = b/d (1)
    Ta có: $\dfrac{a}{b} = \dfrac{c}{d}$
    $\to  \dfrac{a}{b} – 1=\dfrac{c}{d} – 1$
    $\to \dfrac{a – b}{b} = \dfrac{c – d}{d}$
    -> {a – b}/{c – d} = b/d (2)
    (1)(2) ->  {a + b}/{c + d} = {a – b}/{c – d}
    -> {a + b}/{a – b}={c + d} /{c – d}
    Vậy {a + b}/{a – b}={c + d} /{c – d}
    #dariana

Leave a reply

222-9+11+12:2*14+14 = ? ( )

About Nguyệt