0,9х - 0,6х + 1,8 = 0,4х - 2,6 -0,1х = - 4,2 х=42
cosy*<span>√</span>(sinx)=0 (1)
<span>f(x)= 2x^5-3x+11,X=1
</span>f(x)⁾=(2x⁵-3x+11)⁾=2*5x⁵⁻¹- 3*1+0 =10х⁴ -3
f(1)⁾=10*1⁴-3=7
1)cos(π+x)=sinπ/2
-cosx=1
cosx=-1
x=π+2πn
2)sin5xcos4x-cos5xsin4x=1
sin(5x-4x)=1
sinx=1
x=π/2+2πn
3)cosa/(1-sina)=(1+sina)/cosa
cos²a=(1-sina)(1+sina)
cos²a=1-sin²a
cos²a=cos²a
Ctg a = cos a / sin a
cos a - sin a * cos a / sin a= cos a - cos a = 0