代数式4x^2-48xy+144y^2,x^2-6y,x-6xy的和为S,试将S因式分解,当x=1,y=6时,S的值为多少
问题描述:
代数式4x^2-48xy+144y^2,x^2-6y,x-6xy的和为S,试将S因式分解,当x=1,y=6时,S的值为多少
答
S=5x²-54xy+144y²+x-6y
=(x-6y)(5x-24y)+(x-6y)
=(x-6y)(5x-24y+1)
=(1-36)×(5-144+1)
=4830