(1/25)^x-26(1/5)^x+25 меньше =0

сделаем замену y=(1/5)^x y^2-26y+25<=0 решим уравнение y^2-26y+25=0 D=26^2-4*25=576, √D=24 y1=1 и y2=25 ответ для нераенства с y 1<=y<=25 1<=(1/5)^x<=25 ln1<=ln(1/5)^x<=ln25 ln1<=x*ln(1/5)<=2*ln5 ln1<=x*ln5^-1<=2*ln5 ln1<=-x*ln5<=2*ln5 -ln1/ln5>=x>=-2*ln5/ln5 -log₅1>=x>=-2 -2<=x<=-log₅1