kazah
válasza
2 éve
a,
2a-1+4b-a+3b+6-4a-10b+3a-2 = (2a-a-4a+3a)+(4b+3b-10b)+(-1+6-2) = 0a-3b+3 = 3b+3 = `3*2/3+3` = 2+3 = 5
b,
2b+5-2a+4a-3b-1+4b-3a-7-3b = (-2a+4a-3a)+(2b-3b+4b-3b)+(5-1-7) = -a-0b-3 = `-(-2)-3` = 2-3 = -1
c,
`(3a-2)*(a-1)-3a^2+3a-1` = `cancel(3a^2)-3a-2a+2-cancel(3a^2)+3a-1` = `(-3a-2a+3a)+(2-1)` = -2a+1 = `-2*(-2)+1` = 4+1 =5
d,
`(4a-b)*(2a+1)-(8a+3)*(a+2)-2b+2ab` = `cancel(8a^2)-cancel(2ab)+4a-b-cancel(8a^2)-16a-3a-6-2b+cancel(2ab)` = (4a-16a-3a)+(-b-2b)+6 = -15a-3b-6 = `-15*(-2)-3*(2/3)-6` = 30-2-6 = 22
e,
`(3a-2)*(2a-b)-6(a-3)*(a+b)-b*(11-9a)` = `cancel(6a^2)-4a-3ab+2b-cancel(6a^2)-6ab+18a+18b-11b+9ab` = `(-4a+18a)+(-3ab-6ab+9ab)+(2b+18b-11b) = 14a+9b = `14*(-2)+9*2/3` = -28+6 = -22
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kazah
válasza
2 éve
1130,
a,
`3a-2a^2-4+a^2+a-4a^2-5a+1-a^2+2a` = `(-2a^2+a^2-4a^2-a^2)+(3a+1a-5a+2a)+(-4+1)` =
= `-6a^2+a-3`
b,
`3b-b^3+4b^2-1+4b^3-2b^2-4b+2-2b^3-b^2+b-4+2b^2` =
= `(-b^3+4b^3-2b^3)+(4b^2-2b^2-b^2+2b^2)+(3b-4b+b)+(-1+2-4)` =
= `b^3+3b^2-3`
c,
`3cd^2-4c^2+d+2c^2-d^2c+5d-4cd^2+3-d-c^2-cd^2` =
= `(3cd^2-4cd^2-cd^2-cd^2)+(-4c^2+2c^2-c^2)+(d+5d-d)+3` = `-3cd^2-3c^2+5d+3`
d,
`(3a^2-2a+1)-(a^2-a-3)-(a^2+5a-2)` =
= `(3a^2-a^2-a^2)+(-2a+a-5a)+(1+3+2)` = `a^2-6a+6`
e,
`(2x^2-x-3)-(x^2-3x-4)-(-2x^2+4x+1)-(3x^2-2x-1)` =
= `(2x^2-x^2+2x^2-3x^2)+(-x+3x-4x+2x)+(-3+4-1+1)` = `0x^2+0x+1` = 1
f,
`2*(a^2-a+1)+3*(a^2+2a-3)-4*(a^2+3a+4)` = `2a^2-2a+2+3a^2+6a-9-4a^2-12a-16` =
= `(2a^2+3a^2-4a^2)+(-2a+6a-12a)+(2-9-16)` = `a^2-8a-23`
g,
`2*(x^3-2x^2+2)+3*(x^2+x-1)-4*(x^3-2x^2+4x-1)-(x^3-x^2+x+1)` =
= `2x^3-4x^2+4+3x^2+3x-3+4x^3+8x^2-16x+16-x^3+x^2-x-1` =
= `(2x^3-4x^3-x^3)+(-4x^2+3x^2+8x^2+x^2)+(3x-16x-x)+(4-3+4-1)` =
= `-3x^3+8x^2-14x+4`
h,
`3x*(2x^2-x+2)-2x^2*(3x-2)-3*(x^3+2x^2+x-4)-x*(x^2-x-3)+4x^3` =
= `6x^3-3x^2+6x-6x^3+4x^2-3x^3-6x^2-3x+12-x^3+x^2+3x+4x^3` =
= `(6x^3-6x^3-3x^3-x^3+4x^3)+(-3x^2+4x^2-6x^2+x^2)+(6x-3x+3x)+12` =
= `0x^3-4x^2+6x+12` = `4x^2+6x+12`
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