Пошаговое объяснение:
\ begin {gather} sin \ 2x + sin \ 6x = 0 \\ 2sin \ frac {2x + 6x} {2} cos \ frac {2x-6x} {2} = 0 \\ sin \ 4x \ cos \ 2x = 0 \\ \ left [{{sin \ 4x = O} \ atop {cos \ 2x = 0}} \ right. <=> \ left [{{4x = \ pi k} \ atop {2x = \ frac {\ pi} {2} +2 \ pi n}} \ right. <=> \ left [{{x = \ frac {\ pi k} {4} \ atop {x = \ frac {\ pi} {4} + \ pi n}} \ right. => x = \ dfrac {\ pi m} {4} \\ k \ in Z, \ n \ in Z, \ m \ in Z. \ ||| Ombem: \ \ \ dfrac {\ pi m} {4}; \ \ m \ in Z. \ end {gather}% 3D
1) 3 3/23 * 23/27 = 72/23* 23/27= 72/27 = 24/9 = 8/3
2) 1 1/5 * 1/6 = 6/5 * 1/6 = 1/5
3) 14 7/15 - 8/3 = 217/15 - 8/3 = 217/15 - 40/15 = 177/15
4) 177/15 - 1/5 = 177/15 - 3/15 = 174/15 = 11 9/15 = 11 3/5
1) 5 8/9 : 1 17/36 = 53/9 : 53/36 = 4
2) 4 + 1 1/4 = 5 1/4
3) 5 1/4 * 5/21 = 21/4 * 5/21 = 5/4 = 1 1/4
1) - 3,25 - 2,75 = - 6
2) - 6 : - 0,6 = 10
3) 0,8 * - 7 = - 5,6
4) 10 + (- 5,6) = 10 - 5,6 = 4,4
1) - 1 3/8 - 2 5/12 = - 11/8 - 29/12 = - 33/24 - 58/24 = - 91/24
2) - 91/24 : 5 5/12 = - 91/24 : 65/12 = - 91/130 = - 7/10
Пошаговое объяснение: