20-4×p×22×p=
20-88×p×p=
20-88×(12,25)=
-1058
504 = 2*2*2*3*3*7
8281=7*7*13*13
108000=2*2*2*2*2*3*3*3*5*5*5
12321=3*3*37*37
А) f(-1) = 5(-1)^2 -3 *(-1) -1 = 5*1+3-1 = 7
б) 1 = 5x^2-3x-1
5x^2-3x-1-1 = 0
5x^2 -3x-2 = 0
D = (-3)^2 - 4·5·(-2) = 9 + 40 = 49
x1 = (3 - √49)/2·5 = (3 - 7)/10 = -4/10 = -0.4
x2 = (<span><span>3 + √49)/</span>2·5</span> = (<span>3 + 7)/10</span> = <span>10/10</span> = 1
в) х=0 у= 1
1 = 5*0^2-3*0-1
1≠ -1 нет