Bài 2: Tìm x. a ) (x + 3)(x - 3) - (x - 2)(x + 5) - Dicamon

Question

Bài 2: Tìm x. a ) (x + 3)(x - 3) - (x - 2)(x + 5) = 6 c ) 4x ^ 2 - 9 = 0 b) 2x ^ 2 + 3(x - 1)(x + 1) = 5x(x + 1) d ) 4 * (5 - 2x) ^ 2 - 16 = 0

Answer

a ) ( x + 3 ) ( x 3 ) ( ) ( x + 5 ) = - + 2x + 10-6 - 3x = 5 = 5 3 b ) ( x ^ 2 + 3(x - 1)(x + 1) = 5x(x + 1); 2x ^ 2 + 3(x ^ 2 - 1) - 5x ^ 2 - 5x = + 5 -5x 3 - 5x = 3 G 3 5

Answer

H 2x ^ 2 + 3(x + 1) ) 5x (x+1 ) 2x ^ 2 + b(x ^ 2 - 1); =5x^ 2 +5x; 2x ^ 2 + 3x ^ 2 = 3; 5x ^ 2 + 5x; 5x ^ - 2 - 3; =5x^ 2 +5x d ) 4 * (5 - 2x) ^ - 2 - 16 = 0; 4(25 - 20x + 4n ^ 2)

giải giúp tớ câu b với câu d ạ tớ cảm ơn