wykonaj mnożenie i zredukuj wyrazy podobne.

a) (3a+4)(a-5)=
b) (2t+1)(1-3t)=
c) (3ab-7)(3-7ab)=
d) (x-y)(5x+6y)=
e) (x+5y)(7x-y)=
f) (ab-a)(2ab+6a)=


Odpowiedź :

a) (3a+4)(a-5)=3a^2-15a+4a-20=3a^2-11a-20
b) (2t+1)(1-3t)=2t-6t^2+1-3t=-6t^2-t+1
c) (3ab-7)(3-7ab)=9ab-21a^2b^2-21+49ab=-21a^2b^2+58ab-21
d) (x-y)(5x+6y)=5x^2+6xy-5xy-6y^2=5x^2-6y^2+xy
e) (x+5y)(7x-y)=7x^2-xy+35xy-5y^2=7x^2-5y^2+34xy
f) (ab-a)(2ab+6a)=2a^2b^2+6a^2b-2a^2b-6a^2=2a^2b^2+4a^2b-6a^2

^2 do potęgi 2(kwadratu)wiec jak jest tak 2a^2bto to jest 2 razy a do kwadratu razy b
a) (3a+4)(a-5)= 3a do kwadratu-15a+4a-20=-11a=3a do kwadratu+4a
b) (2t+1)(1-3t)=2t +6t do kwadratu +1-3t= -t+1+6t do kwadratu
c) (3ab-7)(3-7ab)=9ab - 21 a do kwadratu b do kwadratu-21+49ab
58ab- 21 a do kwadratu b do kwadratu-21
d) (x-y)(5x+6y)= 5xdo kwadratu +6xy-5xy-6y do kwadratu= 5xdo kwadratu +xy-6ydo kwadratu
e) (x+5y)(7x-y)= 7xdo kwadratu -xy+35xy-5y
f) (ab-a)(2ab+6a)= 2ado kwadratu b do kwadratu+6a do kwadratu b-2 a do kwadratu b - 6a do kwadratu= 4a do kwadratu b + 2ado kwadratu b do kwadratu -6a do kwadratu
a)=3a²-15a+4a-20=3a²-11a-20
B)=2t-6t²+1-3t=-6t²-t+1
c)=9ab-21a²b²-21+49ab=-21a²b²+58ab-21
d)=5x²+6xy-5xy-6y²=5x²+xy-6y²
e)=7x²-xy+35xy-5y²=7x²-5y²+34xy
f)=2a²b²+6a²b-2a²b-6a²=2a²b²+4a²b-6a²