<span>х²-10х+9 =
D = 100-36 = 64 (8)
x1 = (10+8):2 = 9
х2 = (10-8):2 = 1
</span><span>х²-10х+9 = (х-9)*(х-1)</span>
Всё просто :) 3^6.8*3^-5.8=3^1=3 :)
^ - показатель степени.
<span>1)(2x-3)(x+5)-2=11-(x-4)^2
2x^2-3x+10x-15=11-x^2+8x-16
</span><span>2x^2-3x+10x-15-11+x^2-8x+16=0
3x^2-x-10=0
</span><span>2)(5x-1)(5x+1)+20x^2=7x-3
</span><span>25x^2-1+20x^2-7x+3=0
</span>45x^2+-7x+2=0<span>
</span><span>3)(8-x)(8+x)+(1-4x)^2=12x^2+1
</span><span>64-x^2+1-8x+16x^2-12x^2-1=0
</span><span>13x^2-8x+64=0
</span><span>
16</span>
А) 31 - 2z = 15
2z=31-15
2z=16
z=16/2=8;
<span>б) 3 + 0.1x = 4
0,1x=4-3
0,1x=1
x=1/0,1=10.</span>
<span> log₃(3-x)=3</span>