Odpowiedź :
Zadanie 1.
a)
[tex](x+7y)^2=x^2+2x\cdot 7y+(7y)^2=x^2+14xy+49y^2[/tex]
b)
[tex](2x+3y^2)^2=(2x)^2+2\cdot 2x\cdot3y^2+(3y^2)^2=4x^2+12xy^2+9y^4[/tex]
c)
[tex]\left(\dfrac12+2y\right)^2=\left(\dfrac12\right)^2+2\cdot\dfrac12\cdot 2y+(2y)^2=\dfrac14+2y+4y^2[/tex]
d)
[tex](x^2+3y^2)^2=(x^2)^2+2\cdot x^2\cdot 3y^2+(3y^2)^2=x^4+6x^2y^2+9y^4[/tex]
e)
[tex]16x^2-25y^2=(4x)^2-(5y)^2=(4x-5y)(4x+5y)[/tex]
f)
[tex](a+b)^2=a^2+2ab+b^2[/tex]
g)
[tex](a-b)^2=a^2-2ab+b^2[/tex]
Zadanie 2.
a)
[tex]2x^2-x^4+8x^3+8x^4-10+2x^4+15x^3=9x^4+23x^3+2x^2-10[/tex]
b)
[tex]7x^3-12x+14x^3-2x^3+15x+100=19x^3+3x+100[/tex]
c)
[tex]21x^2-(x^2+5x+3x+15)=21x^2-x^2-8x+15=20x^2-8x+15[/tex]
d)
[tex]14x-2(x+5)+3(x-1)-8(x^2+5)+100=14x-2x-10+3x-3-8x^2-40+100=\\=-8x^2+15x+47[/tex]