Ответ:3) 16; 4)√x-√y;
Объяснение:
3)
1) (6^1/2+2^1/2)²=(6^1/2)²+2×6^1/2×2^1/2+(2^1/2)²=6+2×(12)^1/2+2=8+2×(12)^1/2
2) (6^1/2-2^1/2)²=(6^1/2)²-2×6^1/2×2^1/2+(2^1/2)²=6-2×(12)^1/2+2=8-2×(12)^1/2
3) 8+2×(12)^1/2+(8-2×(12)^1/2)=8+2×(12)^1/2+8-2×(12)^1/2=16
4) (x-y)/(x^1/2+y^1/2)=(x^1/2+y^1/2)×(x^1/2-y^1/2)/(x^1/2+y^1/2)=x^1/2-y^1/2=√x-√y;
sin5x* cosx - cos5x * sinx = 1
По формуле сложения синусов
sin(5x + x) = 1
sin6x = 1
6x = pi/2 + 2pi*n
x = pi/12 + pi * n/ 3
№8 х² - 1 ≥ 0
Ответ: (-∞; -1] ∪ [1; + ∞)
№ 9
АС = 40, ⇒AM = MC = BC, ⇒ΔMBC - равносторонний.
ΔBHC - прямоугольный. По т. Пифагора BH² = 20² - 10² = 300
BH = √300 = 10√3
№10
дуга АВ = 180°, ∠NBA = 32°, ⇒ дуга AN = 64°
дуга NB = 180° - 64° = 116°, ⇒∠NMB = 116°: 2 = 58°
1) (a+3)²+х+1)²=а²+6а+9+х²+2х+1=а²+6а+х²+2х+10;<span /><span>
2) 2·(m+1)²+3·(m+2)²=2·(m²+2m+1)+3·(m²+4m+4)=</span>2m²+4m+2+3m²+12m+12=5m²+16m+14