В) 14 21 31 42 51 63 68 75
г) 21 31 63 75
номер 211
1) 8
2) 12
3) 15
4) 27
номер 224
1)3/5
2)7/8
3)4/5
4)7/10
5)1/2
6)1/3
7)2/13
8)1/8
9)3/10
12/12 - 1/12 = 11/12 (розовая лента)
6/6 - 5/6 = 1/6 (синяя лента)
9/9 - 4/9 = 5/9 (зелёная лента)
Решение
<span>(4x+3)(4x-3)-(6x-1)^2+18=0
</span><span>16x</span><span>² - 9 - 36x</span><span>² + 12x - 1 + 18 = 0
</span><span>- 20x</span><span>² + 12x + 8 = 0
</span><span>4x</span><span>² - 6x - 4 = 0
</span><span>2x² - 3x - 2 = 0
</span><span>D = 9 + 4*2*2 = 25
</span><span>x₁ = (3 - 5)/4
</span><span>x₁ = -1/2
</span><span>x₂ = (</span><span> 3 + 5)/4
</span><span>x</span><span>₂ </span><span>= 2
</span><span>Ответ: </span><span>x₁ = -1/2 ; </span><span>x₂ </span><span>= 2</span>
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