sin3x*cos3x=sin(3x+3x)/2+sin(3x-3x)/2=sin(6x)/2=1/2*sin6x
а) 7(а³)²=7а⁶
б) (2³×5²×b³)² = (8×25×b³)² = (200×b³)² = 200²×b⁶ = 40000b⁶
в) (10²)³×c×(9d) = 10⁶×c×9d = 9000000cd
г) 6x²×7x³ = 42x⁵