Tga - ctga = 4
(tga - ctga)² = 4²
tg²a - 2tga*ctga + ctg²a = 16 tga * ctga = 1
tg²a - 2 * 1 + ctg²a = 16
tg²a - 2 + ctg²a = 16
tg²a + ctg²a = 16 + 2
tg²a + ctg²a = 18
(x^2-25)/(x^3+4x+25)= (x-5)*(x+5)/(x+5)*(x^2-x+5)= (x-5)/(x^2-x+5)
Ответ:
Объяснение:
(10-√2)²+5√32=100-2*10*√2+(√2)²+5*√(16*2)=100-20√2+2+5*4√2=
=102-20√2+20√2=102.