5x^2*(-3*X^3)^2= -5x^2*9X^6=-45X^8
.......Решение на фото :)
350 - 100%
315 - х%
350х = 315*100
350х=31500
х= 31500/350
х=90%
2cos^3x=cos(-x)
2cos^3x=cosx
2cos^3x-cosx=0
cosx(2 cos^2x-1)=0
<span>
cosx=0
</span><span>x= π/2 + 2πk </span><span>
и</span>
2
cos^2x-1=0
2 cosx=1
<span>
сosx=1/2</span>
<span>x=π/6+2πk
</span>x=5π/6+2πk
<span>Ответ<span>: π/2
+ 2πk ; π/6+2πk ; 5π/6+2πk</span></span>
1) y=4x-3
При х=1, y=4*1-3=1
2) При y=-7,
-7=4x-3
-4x=4
x=-1