A) <span>(5х-2)(5х+2)-(5х-1)^2=4
25x^2-4-25x^2+10x-1=4
10x-5=4
10x=9
x=0.9
б) </span><span>100х^2-16=0
100x^2=16
10x=4
x= 0.4</span>
<span>РЕ\ешение:
18y-3y+y = y(18-3+1)</span>
У(-х)=3*(-х)^4-4*(-х)^2+1=3х^4-4х^2+1=у(х) - функция четная
1. (1 - cos^2t / 1-sin^2t) + tgt*ctgt = 1 / cos^2t
sin^2t / cos^2t + 1 = (sin^2t + cos^2t) / cos^2t = 1 / cos^2t
1/cos^2t = 1/cos^2t
2. sint = -15/17
cos^2t = 1 - sin^2t = 1 - 225/289 = 64/289
cost = -8/17
tgt = sint/cost
tgt = 15*17/17*8 = 15/8
ctgt = 1/tgt = 8/15
В8=в1*q^7=3
b6*b7*b8*b9*b10=
b*q^5*b*q^6*b*q^7*b*q^8*b*q^9=
(b*q^7) ^5=3^5=243