=(2a-3+a)(4a^2+9-6a+a^2-2a^2-3a)
=(2a-3+a)(3a^2-9a+9)
=3(2a-3+a)(a^2-3a+3)
Track 2: (7a+8) 3-c 3
=(7a+8-c)[(7a+8)^2+c^2+c(7a+8)]
The third way: (1-a 2) (1-b 2)-4ab.
=( 1-a^2-b^2+a^2b^2)-4ab
= 1+a^2b^2-2ab-(a^2+b^2+2ab)
=(ab- 1)^2-(a+b)^2
=(a b+ a+b- 1)(a B- a-b- 1)
The fourth lane: (ax+by) 2+(ay-bx) 2
=a^2x^2+b^2y^2+2abxy+a^2y^2+b^2x^2-2abxy
=a^2x^2+b^2y^2+a^2y^2+b^2x^2
=a^2(x^2+y^2)+b^2(x^2+y^2)
=(a^2+b^2)(x^2+y^2)
Track 5:a4+a4 2B 2+B4
=a^4+2a^2b^2+b^4 -a^2b^2
=(a^2+b^2)^2-(ab)^2
=(a^2+b^2+ab)(a^2+b^2-ab)
Track 6: X 4-27x 2+ 1
=x^4-2x^2+ 1-25x^2
=(x^2- 1)^2-(5x)^2
==(x^2+5x- 1)(x^2-5x- 1)
Track 7: A 2-B 2-C 2+D 2-2 (AD+BC)
=a^2-b^2-c^2+d^2-2ad-2bc
=a^2+d^2-2ad-(b^2+c^2+2bc)
=(a+d)^2-(b+c)^2
=(a+b+c+d)(a-b-c+d)
The eighth lane: a 2-4ab+3b 2+2bc-c 2
=a^2-4ab+(4b^2-b^2)+2bc-c^2
=a^2-4ab+4b^2-(b^2-2bc+c^2)
=(a-2b)^2(b-c)^2
=(a-2b+b-c)(a-2b-b+c)
=(a-b+c)(a-3b+c)
Track 9: x 2+6xy-9 1y 2
=x^2+6xy+9y^2- 100y^2
=(x+3y)^2-( 10y)^2
=(x+3y+ 10y)(x+3y- 10y)
=(x+ 13y)(x-7y)
Orbit 10: Y 4-3Y 3-28Y 2
=y^2(y^2-3y-28)
=y^2(y+4)(y-7)
What are the "One" undergraduate courses in primary education?
Main course: