X^3-3x^2+9x+3x^2-9x+27
x^3+27
(1/2)^3+27
1/8+27=27.125
<span>-a^4-0,8a^6-0,16a^8 = - (a^2+0.4)^2
2) 121m^2-44mn+16n^2. = (11m-4n)^2
3) -a^6+4a^3b-4b^2. =-(a^3-2b)^2
5) 80xy+16x^2+25y^2=(4x+5y)^2
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(a+-b)^2=a^2+-2ab+b^2</span>
a1=2+3=5
a2=2*2+3=7
d=a2-a1=7-5=2
S50=)(2*5+2(50-1))50)/2=1850
S100=((2*5+2(100-1))100)/2= 12400
<span>y</span>² <span>+ (2x-y) (2x+y) = у</span>² + (2х)² - у² = 4х²