What is the formula to find the angle between the planes a1x + b1y + c1z + d1 = 0 and a2x + b2y + c2z + d2 = 0?

Question

TuteeHUB · Accepted Answer

sec  =  (  frac {a1a2+b1b2+c1c2}{  sqrt {a1^2+b1^2+c1^2}   sqrt{a2^2+b2^2+c2^2 }}  )

TuteeHUB · Answer

cos  =  (  frac {a1a2+b1b2+c1c2}{  sqrt {a1^2+b1^2+c1^2}   sqrt {a2^2+b2^2+c^2 }}  )

TuteeHUB · Answer

sec  =  (  frac {a1a2+b1b2+c1c2}{  sqrt {a1^2+b1^2+c1^2}   sqrt{a2^2+b2^2+c2^2 }}  )

TuteeHUB · Answer

cos  =  (  frac {a1a2.b1b2.c1c2}{  sqrt {a1^2+b1^2+c1^2}   sqrt{a2^2+b2^2+c2^2 }}  )

TuteeHUB · Answer

cot  =  (  frac {a1a2+b1b2+c1c2}{  sqrt {a1^2+b1^2+c1^2}   sqrt{a2^2+b2^2+c2^2 }}  )

1.	What is the formula to find the angle between the planes a₁x + b₁y + c₁z + d₁ = 0 and a₂x + b₂y + c₂z + d₂ = 0?
A.	cos = ( frac {a1a2+b1b2+c1c2}{ sqrt {a1^2+b1^2+c1^2} sqrt {a2^2+b2^2+c^2 }} )
B.	sec = ( frac {a1a2+b1b2+c1c2}{ sqrt {a1^2+b1^2+c1^2} sqrt{a2^2+b2^2+c2^2 }} )
C.	cos = ( frac {a1a2.b1b2.c1c2}{ sqrt {a1^2+b1^2+c1^2} sqrt{a2^2+b2^2+c2^2 }} )
D.	cot = ( frac {a1a2+b1b2+c1c2}{ sqrt {a1^2+b1^2+c1^2} sqrt{a2^2+b2^2+c2^2 }} )
Answer» B. sec = ( frac {a1a2+b1b2+c1c2}{ sqrt {a1^2+b1^2+c1^2} sqrt{a2^2+b2^2+c2^2 }} )

What is the formula to find the angle between the planes a₁x + b₁y + c₁z + d₁ = 0 and a₂x + b₂y + c₂z + d₂ = 0?