№452. 1)=
![a^{2}](https://tex.z-dn.net/?f=+a%5E%7B2%7D+)
+
![b^{2}](https://tex.z-dn.net/?f=+b%5E%7B2%7D+)
+2ab-4ab=
![a^{2}](https://tex.z-dn.net/?f=+a%5E%7B2%7D+)
+
![b^{2}](https://tex.z-dn.net/?f=+b%5E%7B2%7D+)
-2ab; =
![a^{2}](https://tex.z-dn.net/?f=+a%5E%7B2%7D+)
+
![b^{2}](https://tex.z-dn.net/?f=+b%5E%7B2%7D+)
-2ab =
![a^{2}](https://tex.z-dn.net/?f=+a%5E%7B2%7D+)
+
![b^{2}](https://tex.z-dn.net/?f=+b%5E%7B2%7D+)
-2ab; Доказано
2) =
![a^{2} + b^{2} -2ab + 4ab = a^{2} + b^{2} -2ab;](https://tex.z-dn.net/?f=+a%5E%7B2%7D+%2B++b%5E%7B2%7D+-2ab+%2B+4ab+%3D++a%5E%7B2%7D+%2B++b%5E%7B2%7D+-2ab%3B+)
Доказано.
P.S. Там в 1 и 2 еще сократить нужно, для того чтоб было верным. Ты уже сама справишься)
1) 2а-3b-(4a+7b+c+3) = 2a - 3b - 4a - 7b - c - 3 = -2a - 10b - c - 3<span>2) 2xy-y^2+(y^2-xy)-(x^2+xy) = 2xy - y^2 + y^2 - xy - x^2 - xy = -x^2
</span><span>3) (-2x^2+x+1)-(x^2-x+7)-(4x^2+2x+8) = -2x^2 + x + 1 - x^2 + x - 7 - 4x^2 - 2x - 8 = -7x^2 -14 = -7(x^2 + 2)
</span><span>4) (3a^2-a+2)+(3a^2+3a-1)-(a^2-1) = 3a^2 - a + 2 + 3a^2 + 3a - 1 - a^2 + 1 = 5a^2 + 2a + 2
</span><span>5) (1-x+4x^2-8x^3)+(2x^3+x^2-+x-3)-(5x^3-8x^2) = 1 - x + 4x^2 - 8x^3 + 2x^3 + x^2 + x - 3 - 5x^3 + 8x^2 = -11x^3 + 14x^2 - 2
</span><span>6) (0.5a-0.6b+5.5)-(-0.5a+0.4b)+(1.3b-4.5) = 0.5a - 0.6b + 5.5 + 0.5a - 0.4b + 1.3b - 4.5 = a + 0.3b + 1
</span><span>7) (x^2)^4*(x^4)^3 = x^8 * x^12 = x^(8 + 12) = x^20
</span><span>8) (a^2*a^3)^4 = a^4(2 + 3) = a^(4*5) = a^20</span>