2)1.3х+1=2.3
2.3*2=4.6
4.6-1.2=-34
34-27.04=-23.64
23.64:5.6=4.2
sin^2 4x + cos^2 4x - (cos^2 4x - sin^2 4x)=sin 4x
sin^2 4x +cos^2 4x - cos^2 4x + sin^2 4x=sin 4x
2sin^2 4x - sin 4x=0
sin 4x(2sin 4x-1)=0
sin 4x =0 sin 4x=1/2
4x=πn, n∈ Z 4x=(-1)^k *π/6 +πk,k∈ Z
x =πn/4,n∈ Z x=((-1)^k*π)/24 +πk/4,k∈ Z
(a^2-2b)^2=a^4-4a^2b+4b^2
<span>(8x+x^3)^2=64x^2+16x^4+x^6</span>