Question

please answer..19th question

Answer 1

Answer:

2 & 4/5 respectively

Step-by-step explanation:

1.  [{sec²∅-cot²(90-∅)} / {cosec²67-tan²23}] + [sin²40+sin²50]

=[{sec²∅-tan²∅}/{cosec²67-tan²(90-67)}] + [sin²40+sin²(90-40)]

=[1/{cosec²67-cot²67}] + [sin²40+cos²40]

=[1/1] + [1]  = 1 + 1   = 2

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2.   3 tan∅=4

∴tan∅=4/3

=(4 cos∅-sin∅)/(2 cos∅+sin∅)

=(4 cos∅-sin∅)/(2 cos∅+sin∅)×{(1/cos)/(1/cos)}

=(4-tan∅)/(2+tan∅)

=(4-(4/3))/(2+(4/3))

=(8/3)/(10/3)

=8/10  -= 4/5