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 8: a, x^3+(1/3)^3 b, 8x^3-(1/2)^3

Toán Lớp 8: a, x^3+(1/3)^3
b, 8x^3-(1/2)^3

Comments ( 2 )

  1. a) x³+($\dfrac{1}{3}$)³
    = (x+$\dfrac{1}{3}$)(x²-x$\dfrac{1}{3}$+$\dfrac{1}{9}$)
    Áp dụng hằng đẳng thức là :
    A³ + B³ = (A + B)(A² – AB + B²)
    b) 8x³-($\dfrac{1}{2}$)³
    = (2x)³-($\dfrac{1}{2}$)³
    = (2x-$\dfrac{1}{2}$)(4x²-x+$\dfrac{1}{4}$)
    Áp dụng hằng đẳng thức là :
    A³ – B³ = (A – B)(A² + AB + B²)

  2. a, = (x+$\dfrac{1}{3}$ ).( + x + ^ + 2 ++ $\dfrac{1}{3}$ x + $\dfrac{1}{9}$ )
    b = (2x)^3 – (1/2)^3

Leave a reply

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