Apartado 1xy2- 15x = x(y2-15)(x)(y2) = xy2 (x)(-15) = -15xApartado 22x(a -1) -3y(a -1) = (2x-3y)(a-1)Apartado 325a2-144b2 = (5a+12b)(5a-12b)(5a)(5a)=25a2 (5a)(-12b)=-60ab (12b)(5a)=60ab (12b)(-12b)=-144b225a2-60ab+60ab-144b2Apartado 4p(q+1)-r(q+1) = (p-r)(q+1)Apartado 58a3-64b3 = (2a+4b)(4a2+8ab-16b2)(2a)(4a2) = 8a3 (2a)(+8ab)=16 a2b (2a)(-16b2)=-32ab2 (4b)(4a2)=16a2b (4b)(+8ab)= +32ab2 (4b)(-16b2)=-64b38a3 + 16a2b -32ab2 - 16a2b +32ab2 -64b3