Finding cartesian equation of plane

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To find the Cartesian equation of a plane through the points (3,0,1) and (0,1,-1), and perpendicular to the plane defined by x-y-z+1=0, the normal vector must satisfy the dot product condition with (1,-1,-1). The equation can be expressed in standard form, requiring that both points lie on the plane. By substituting the coordinates of the points into the equation, simultaneous equations can be formed to solve for the coefficients a, b, and c. Ultimately, any scalar multiple of the normal vector will represent the same plane, allowing flexibility in selecting values for a or b. The discussion emphasizes the importance of satisfying the conditions for the plane's equation.
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Homework Statement


determine the Cartesian equation of the plane through the points (3,0,1) and (0,1,-1) and perpendicular to the plane with equation x-y-z+1 = 0



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The Attempt at a Solution


Well I know the normal of the plane (a,b,c) dotted with (1,-1,-1) = 0 which gives me a-b-c=0
but other than that I am stuck
 
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You need to write out the description in terms of the maths.
You know the standard form for the cartesian equation of the plane (or the vetor form - whichever you are most comfortable with). So write it out.

That equation has to satisfy some conditions - write out what those mean.

i.e. point (3,0,1) is on the plane - so if you put x=3, y=0, z=1 into the equation, how does it come out?

The rest is simultaneous equations.
 
(a, b, c).(0, 1,-1)= b- c= 0 so you know b= c. The equation must be of the form a(x- 3)+ by+ b(z- 1)= 0 and you know that x= 0, y= 1, z= -1 must satisfy that: -3a+ b- 2b= 0. Of course, any multiple of (a, b, c) will give the same plane so you can take either a or b to be whatever you like.
 
Ok, thanks
 
Lucky person you - HoI does not normally do people's homework for them...
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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