Toán Lớp 8: Khai triển : (a+2/3 )^2 .(a-2/3)^2 Ma' mất oan 10 đ :'))

Question

Toán Lớp 8:  Khai triển : (a+2/3 )^2 .(a-2/3)^2 Ma' mất oan 10 đ :'))

minhtuyethue · Answer

(a+2/3)^2 (a-2/3)^2   =[(a+2/3)(a-2/3)]^2   =[a^2-(2/3)^2]^2   =(a^2-4/9)^2   =(a^2)^2 - 2.a^2 . 4/9 +(4/9)^2   =a^4-8/9a^2+16/81

quynhmaithu · Answer

Giải đáp:    (a + 2/3)^2 . (a - 2/3)^2    = [ (a + 2/3) . (a - 2/3)]^2    = [ a^2 - (2/3)^2]^2    = (a^2 - 4/9)^2    = a^4 - 8/9a^2 + 16/81

Toán Lớp 8: Khai triển : (a+2/3 )^2 .(a-2/3)^2 Ma’ mất oan 10 đ :’))