F.2 math!!!! Quick!!

1) 81x^2+40x+5,it cannot be factorize
Or 80x^2+40x+5
=5(4x+1)^2

2) -288p^2+18r^2+48pq-2q^2
=2(-144p^2+9r^2+24pq-q^2)
=2(-(12p-q)^2+9r^2)
=2(3r+12p-q)(3r-12p+q)

3) 49a^2-64
=(7a-8)(7a+8)

4) -p^2q^2+r^4
=r^4-(pq)^2
=(r^2+pq)(r^2-pq)

5) a^2-b^2+bc-ac
=(a+b)(a-b)-c(a-b)
=(a+b-c)(a-b)

6) 4c^2-2c-9d^2-3d
=(2c+3d)(2c-3d)-(2c+3d)
=(2c+3d)(2c-3d-1)

1:F2 5會計到~你可能抄錯 答案係
81x^2+40x+5=[9x+20/9-(√-5)/9)][9x+20/9+(√-5)/9]

2: -288p^2+18r^2+48pq-2q^2
=-2(144p^2-24pq+q^2-9r^2)
=-2[(12p-q)^2-(3r)^2]
=-2(12p-q-3r)(12p-q+3r)//

3:49a^2-64
=(7a)^2-8^2
=(7a+8)(7a-8)//

4:-p^2q^2+r^4
=-[(pq)^2-(r^2)^2
= -(pq-r^2)(pq+r^2)
=(r^2-pq)(r^2+pq)//

5:a^2-b^2+bc-ac
=(a+b)(a-b)+c(b-a)
=(a+b)(a-b)-c(a-b)
=(a+b-c)(a-b)//

6:4c^2-2c-9d^2-3d
=4c^2-9d^2-2c-3d
=(2c-3d)(2c+3d)-(2c+3d)
=(2c-3d-1)(2c+3d)//