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I'm stuck on how to approach this. Maybe I can try considering specific values for x, y, z, t and see if they satisfy both equations.
Alternatively, perhaps using some substitution method to reduce the variables. Or maybe think about symmetry or other properties.
Wait, the problem is a system of two equations with four variables. So, it's likely that either no solution exists, infinitely many solutions, or exactly one solution. Since the question is Yes or No, I'm thinking if there is at least one real solution, so answer Yes; otherwise, No.
Let me try plugging in some numbers to see if I can find a solution.
First equation: x^3 + y^3 - 5x = 0
Second equation: y^3 + z^3 - 7t = 0
Hmm. Maybe set t as something simple?
Suppose I let t be zero, then the second equation becomes y^3 + z^3 = 0. That would imply y = -z.
But what about x? Then from the first equation: x^3 + y^3 -5x=0. Let's say x is also zero? If x and y are both zero, but then z would be zero too?
Wait, if x=y=z=t=0, let me check:
First equation: 0 + 0 - 0 = 0 : yes.
Second equation: 0 + 0 - 0 = 0 : also yes. So (0,0,0,0) is a solution. Therefore, there exists at least one real solution, namely the trivial solution where all variables are zero. Thus, the answer would be Yes.
But wait, maybe I missed something? Because the question was about real numbers, and 0 is a real number. So, even if it seems too easy, perhaps that's the only solution?
Wait, but how come two equations with four variables? It could have infinitely many solutions or no solution.
In this case, since substituting x=y=z=t=0 satisfies both equations, at least one solution exists. Therefore, the answer is Yes.
But just to be thorough, let me see if there are any other possibilities.
Alternatively, suppose I solve for t from the second equation: t = (y^3 + z^3)/7
Then plug into first equation:
So, x can be expressed as (from above): x^3 -5x + y^3=0. So depending on y and x, you have solutions?
But since variables are real numbers, maybe for some values of x, there could be multiple ts? But if I set t=(y^3 + z^3)/7, then perhaps different solutions.
Wait, but the question is only whether a solution exists in R, not unique or how many. So even if infinitely many, since existence is enough to answer Yes.
Alternatively, maybe another approach: Let's see if it's possible that some variables are zero.
Suppose x=0. Then first equation becomes y^3 -5*0 =0 ⇒ y^3=0 ⇒ y=0. Then t from second equation would be (y³ + z³)/7=(0 + z³)/7. So, for t to exist as real number, z can be any real number.
But wait, hold on: if x=0 and y=0, then first equation is satisfied. Second equation becomes 0 + z^3 -7t =0 ⇒z^3=7t, so t=z³/7.
Thus, for any z in R, we can set x=0,y=0,z=z,t=z³/7. So, infinitely many solutions: (0,0,z,z³/7), where z is real.
Hence, there are non-trivial solutions as well.
Therefore, since the system allows multiple solutions (infinite ones) and at least one solution exists (trivially), we can confidently say that Yes, such numbers exist.
The problem asks whether the given system of equations has a real number solution. The system is:
1. \( x^3 + y^3 - 5x = 0 \)
2. \( y^3 + z^3 - 7t = 0 \)
To determine if there is a solution, we can test specific values for the variables.
First, consider setting \( x = 0 \) and \( y = 0 \):
- From the first equation: \( 0^3 + 0^3 - 5(0) = 0 \), which is satisfied.
- From the second equation: \( 0^3 + z^3 - 7t = 0 \), which simplifies to \( z^3 = 7t \). This implies that for any real number \( z \), we can set \( t = \frac{z^3}{7} \).
Thus, there are infinitely many solutions of the form \( (0, 0, z, \frac{z^3}{7}) \) where \( z \) is any real number. Additionally, the trivial solution \( x = y = z = t = 0 \) also satisfies both equations.
Therefore, since at least one solution exists, the answer is: