👤

(a+b+8)^2 - (a+b)^2 - 16(a+b-3) = ? Teroc!

Răspuns :

(a+b+8)^2-(a+b)^2-16(a+b-3)=

=a^2+b^2+64+2ab+16a+16b-(a+b)^2-16(a+b-3)

=a^2+b^2+64+2ab+16a+16b-(a^2+2ab+b^2)-16(a+b-3)

=a^2+b^2+64+2ab+16a+16b-(a^2+2ab+b^2)-16a-16b+48

=a^2+b^2+64+2ab+16b-(a^2+2ab+b^2)-16b+48

=a^2+b^2+64+2ab-(a^2+2ab+b^2)+48

=a^2+b^2+64+2ab-a^2-2ab-b^2+48

=b^2+64+2ab-2ab-b^2+48

=64+2ab-2ab+48

=64+48

=112