Question

(1) 7х в кубе-63х=0 (2) (х+3)(х-3)-х(х-4)=0

Answer 1

7x³-63x=0
x(7x²-63)=0
x=0 или 7x²-63=0
             7x²=63
              x²=9
              x= плюс/минус 3

(x+3)(x-3)-x(x-4)=0
(x²-3x+3x-9)-(x²-4x)=0
x²-9-x²+4x=0
4x-9=0
4x=9
x= $\frac{9}{4}$
x=2,25 (Но я сомневаюсь)

Answer 2

Let's solve each equation step by step:

(1) 7x³ - 63x = 0

Factor out x to get:

x(7x² - 63) = 0

Simplify by dividing both sides by 7:

x(x² - 9) = 0

Factor the expression inside the parentheses using the difference of squares:

x(x - 3)(x + 3) = 0

So the solutions are x = 0, x = 3, and x = -3.

(2) (x + 3)(x - 3) - x(x - 4) = 0

Expand the left-hand side using the distributive property:

x² - 9 - x² + 4x = 0

Simplify by combining like terms:

4x - 9 = 0

Add 9 to both sides:

4x = 9

Divide both sides by 4:

x = 9/4 or x = 2.25

Therefore, the solutions are x = 9/4 and x = 2.25.