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9 sec x + 9 tan x = 9

User Myer
by
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1 Answer

13 votes

Answer:

Lowest root is 0 degrees.

Explanation:

divide through by 9:

sec x + tan x = 1

sec^2x = 1 + tan^2 x so

√(1 + tan^2x) + tanx = 1

√(1 + tan^2x) = 1 - tanx

Squaring both sides:

1 + tan^2 x = 1 - 2 tanx + tan^2 x

1 = 1 - 2 tan x

2tanx = 0

x = 0 degree.

User Dertoni
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