1) 14a⁴b / 49a³b² = 2a / 7b3x /(x²+4x) = 3x / (x(x+4)) = 3 / (x+4)(y²-z²) / (2y+2z) = ( (y-z)(y+z) ) / ( 2(y+z)) = (y-z)/2 = 0.5(y-z)2)a) (3x-1)/x² - (x-9)/3x = ( 3(3x-1) - x(x-9) ) / 3x² == (9x-3-x²+9x) /3x² = (-x²+18x-3) /3x² == - (x²-18x+3)/3x²б) 1/(2а-b) - 1/(2a+b) = ((2a+b) - (2a-b)) / ((2a-b)(2a+b) )== (2a+b-2a+b) / ( (2a)² -b²) = 2b/(4a²-b²)в) 5/(c+3) - (5c-2)/(c²+3c) = 5/(c+3) - (5c-2) / (c*(c+3))== (5c -5c+2)/ (c(c+3)) = 2/ (c(c+3)) = 2/ (c²+3c)3)(a²-b)/a - a = (a²-b -a²) /a = -b/aпри а=0,2 ; b=-5- (-5) / 0.2 = - (-25) = 25проверим на полном выражении:( 0,2² - (-5)) /0,2 - 0,2 = (0,04+5)/0,2 -0,2 == 5,04/0,2 -0,2 = 25,2 -0,2 =254) 3/(х-3) - [(х+15) /(х²-9)] - 2/x== 3/(x-3) - [(x+15)/ (x-3)(x+3) ] - 2/x== (3x(x+3) - x(x+15) -2(x-3)(x+3) ) / (x(x-3)(x+3)) == (3x² + 9x - x² - 15x - 2x² +18 ) / (x(x-3)(x+3)) == ( (3x²-x²-2x²) + (9x-15x) +18 ) / (x(x-3)(x+3)) = = (6x+18) / (x(x-3)(x+3)) = (6(x+3) ) / (x(x-3)(x+3)) == 6 / (x(x-3) ) = 6 / (x²-3x)