Question

若-5ab n-1的次方与1/3a m-1的次方 b的3次方是同类项,则m＋2n________

Answer 1

(1)m-1=1 m=2

n-1=3 n=4

m+2n=10

(2)3A-2B=(3x²-9x-18)-(4x²-8x+12)=-x²-x-30

(3)m²=mn+2 n²=mn-5

3m²+2mn-5n²=3(mn+2)+2mn-5(mn-5)=3mn+6+2mn-5mn+25=31