1.cos(3п/8)sin(5п/24) - cos(5п/24)sin(3п/8) 2.tg13+tg32/1-tg13tg32 3.cos(13п/12) - cos (5п/12)

Cos(3п/8)sin(5п/24) - cos(5п/24)sin(3п/8)=sin(3π/8 -5π/24)=sin(4π/24)=sin(π/6)=1/2 (tg13+tg32)/1-tg13tg32=tg(13°+32°)=1 cos(13п/12) - cos (5п/12)=-2  ×sin((13π-5π)/12)  × sin((13π+5π)/12) ==-2 sin(8π/12)×sin(18π/12)=-2sin(2π/3)×sin(3π/2)=-2sin(π-π/3)×(-1)=2×√3/2=√3

по теореме пифагора

x2+(x+7)2=132

x2+x2+14x+49-169=0

2x2+14x-120=0

x2+7x-60=0

по теореме виета:

x1=-12x2=5

ответ5 и 12 см.

всего хорошего

(327x-5295): 57=389

327x-5295=22173

327x=16878

x=16878/327=5626/109 =51 67/109