343y² -(7^3*y^3 +3^3*z^3) = 343y² -343y^3 -27z = 343y²(1 -y) -27z = 343*48²* (1 -48) -27*2/3 = 790 272 * (-47) - 18 = -37 142 802
2x-14=2x+20
2x-2x=20-14
2x и 2x взаимно уничтожаются и остается 6)
30. у=x²+bx+ c y(0)=c=2 -b/2a=-b/2=-2⇒b=4
y=x²+4x+2
33. y=a/x пусть х=1⇒а/1=2 a=2 y=2/x
34. надоело.
1)2^3.9 приближенно 15
<span><span>a<span>log<span>ab</span></span> = b - основное логарифмическое тождество</span><span>loga 1 = 0</span><span>log<span>a a</span> = 1</span><span>log<span>a x · y</span> = log<span>ax</span> + log<span>ay</span></span><span><span><span>loga </span>x<span> = log<span>ax</span> - log<span>ay</span></span></span>y</span><span><span><span>loga </span>1<span> = - log<span>ax</span></span></span>x</span><span>log<span>a xp</span> = p log<span>ax</span></span><span><span><span>log<span><span>ak</span> x</span> = </span>1<span> log<span>a x</span>, при k ≠ 0</span></span>k</span><span>log<span>ax</span> = log<span><span>ac</span> xc</span></span><span><span><span>log<span>a x</span> = </span><span>log<span>b x</span></span><span> - формула перехода к новому основанию</span></span><span>log<span>b a</span></span></span><span><span><span>log<span>a x</span> = </span>1</span><span>log<span>x a</span></span></span></span>
