Tính tích: (-1/2xy) (8x^2 -5xy +2y^2)
Giải thích
Ta có −12xy(8x2−5xy+2y2)
=−12xy . 8x2−−12xy . 5xy+−12xy . 2y2
=−12xy . 8x2+12xy . 5xy−12xy . 2y2
=−4x3y+52x2y2−xy3.
Ta có −12xy(8x2−5xy+2y2)
=−12xy . 8x2−−12xy . 5xy+−12xy . 2y2
=−12xy . 8x2+12xy . 5xy−12xy . 2y2
=−4x3y+52x2y2−xy3.