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प्रश्न
Evaluate:
`cot^2 30^0-2cos^2 30^0-3/4 sec^2 45^0 +1/4 cosec^2 30^0`
उत्तर
On substituting the values of various T-ratios, we get:
`cot^2 30^0-2cos^2 30^0-3/4 sec^2 45^0 +1/4 cosec^2 30^0`
=`(sqrt(3))^2 - 2 xx(sqrt(3)/2)^2 - 3/4 xx(sqrt(2))^2+1/4xx(2)^2`
=`3-2xx3/4-3/4xx2+1/4xx4`
=`3-3/2-3/2+1`
=`4-(3/2+3/2)`
`=4-3=1`
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