Sкруга=πR²
Sкруга/2=πR²/2
8π=πR²/2
R²=16
R=4
V=(4/3)πR³
V=(4/3)π*4³
V=256π/3
<span>(1-3х)(1-4х+х²)+(3х-1)(1-5х+х²)+3х²=
=</span>(1-3х)(1-4х+х²)-(1-3x)(1-5x+x²)+3x²=
=(1-3x)(1-4x+x²-1+5x-x²)+3x²=
=(1-3x)*x+3x²=x-3x²+3x²=x
9/5.5-7/11=90/55-7/11=90/55-35/55=55/55=1
Решение
√13 + √52 = √13 + √(4*13) = √13 + 2√13 = 3√13
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