a. -\(-16x^2+8xy-y^2+49\)
= \(\left(-\left(4x\right)^2+8xy-y^2\right)+49\)
= \(-\left(\left(4x^2\right)-8xy+y^2\right)+49\)
= \(-\left(4x-y\right)^2+49\)
b. \(y^2\left(x^2+y\right)-zx^2-zy\)
= \(y^2\left(x^2+y\right)-z\left(x^2+y\right)\)
= \(\left(x^2+y\right)\left(y^2-z\right)\)
Đúng 0
Bình luận (0)
_16x2+8xy_y2+49
=( _(4x)2+2 × 4 × xy _ y2 )+ 72
= _((4x)2_ 2×4×x × xy +y2)+72
= _(4x_y)2+72
=72_(4x_y)2
= (7_(4x_y))×(7+(4x_y))
= (7_4x+y)×(7+4x_y)
2)y2×(x2+y)_zx2_zy
=y×(x2+y)_z(x2+y)
= ( x2+y)×(y_z)
Đúng 0
Bình luận (0)
