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Question
Evaluate:
`4/(cot^2 30^0) +1/(sin^2 30^0) -2 cos^2 45^0 - sin^2 0^0`
Solution
On substituting the values of various T-ratios, we get:
`4/(cot^2 30^0) +1/(sin^2 30^0) -2 cos^2 45^0 - sin^2 0^0`
=`4/(sqrt(3))^2 + 1/(1/2)^2 -2xx(1/sqrt(2))^2-(0)^2`
=`4/3 +1/(1/4) -2xx1/2-0`
=`4/3 +4-1`
=`4/3+3=(4+9)/3=13/3`
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