Question

without using trignometric table evaluate sin
$\sin^{2} 35 + \sin^{2} 55 \div \sec^{2} 15 - \cot{ {}^{2} } 75 \times \sqrt{3}$
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Answer 1

7/2 cos70/sin(90-70) + 3/2 cos55 cosec(90-55) / tan5 tan(90-65) tan45 tan(90-5) tan65

7/2 cos70/cos70 + 3/2 cos55 sec55/tan5*cot5*tan65*cot65*tan45 ( tan 45 = 1)

7/2+3/2/1*1

10/2 = 5