7) Find the acute angle o such that 2cos²0=
3 sin0
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Answer:
2cos²∅ = 3 sin∅
=> 2( 1 - sin²∅ ) = 3sin∅
=> 2 - 2sin²∅ = 3sin∅
=> 2sin²∅ + 3sin∅ - 2 = 0
=> 2sin²∅ + 4sin∅ - sin∅ - 2 = 0
=> 2sin∅( sin∅ + 2) - 1 ( sin∅ + 2) = 0
=> ( sin∅ + 2)( 2sin ∅ - 1 ) = 0
=> sin∅ + 2 = 0 , or , 2sin∅ -1 = 0
=> sin∅ = -2 , or , sin∅ = ½
but the minimum value of sin∅ is ( -1 )
so, sin∅ = -2 is rejected..
thus,
sin∅ = ½
or , sin∅ = sin30°
OR, ∅ = 30° .
I hope it will help u .
Step-by-step explanation:
formula used ,
cos²∅ = 1 - sin²∅.
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