If (sec A + tan A) (sec B + tan B) (sec C + tan C) = (sec A –tan...
(secA + tanA)(secB + tanB)(secC + tan C)
=> (secA - tanA)(secB - tanB)(secC - tanC)
{ Mulitply both sides with }
(secA + tanA)(secB + tanB)(secC + tan C)",
we get,
(secA + tanA)2(secB + tanB)2(secC + tan C)2
=> (sec2A - tan2A)(sec2B - tan2B)(sec2C - tan2C)
= (1)(1)(1) = 1
=> [(secA + tanA)(secB + tanB)(secC + tanC)]2=1
(secA + tanA)(secB + tanB)(secC + tan C) = ± 1
Similarly, we get
(secA – tanA)(secB – tanB)(secC – tan C) = ± 1
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If (sec A + tan A) (sec B + tan B) (sec C + tan C) = (sec A –tan...
Tan A) (sec B tan B) (sec C tan C), then we can conclude that sec A tan A = sec B tan B = sec C tan C.
To prove this, let's assume that sec A tan A ≠ sec B tan B. Without loss of generality, let's assume that sec A tan A > sec B tan B.
Then, we have sec A tan A (sec B tan B) (sec C tan C) > sec B tan B (sec B tan B) (sec C tan C).
Simplifying the above expression, we get sec A tan A (sec B tan B) (sec C tan C) > sec B^2 tan^2 B (sec C tan C).
Since sec B^2 tan^2 B = sec B tan B (sec B tan B), we can rewrite the expression as sec A tan A (sec B tan B) (sec C tan C) > sec B tan B (sec B^2 tan^2 B (sec C tan C)).
Using the given equality, we can substitute sec A tan A = sec B tan B, giving us sec B tan B (sec B tan B) (sec C tan C) > sec B tan B (sec B^2 tan^2 B (sec C tan C)).
Cancelling out sec B tan B from both sides, we are left with sec B tan B (sec C tan C) > sec B^2 tan^2 B (sec C tan C).
Dividing both sides by sec C tan C (which is not equal to zero), we get sec B tan B > sec B^2 tan^2 B.
Simplifying the expression, we have 1 > sec B tan B, which is not possible since sec B tan B is always greater than or equal to 1.
Therefore, our assumption that sec A tan A ≠ sec B tan B must be false, and we can conclude that sec A tan A = sec B tan B.
Similarly, we can prove that sec A tan A = sec C tan C.
Hence, if (sec A tan A) (sec B tan B) (sec C tan C) = (sec A tan A) (sec B tan B) (sec C tan C), we can conclude that sec A tan A = sec B tan B = sec C tan C.