Question
If 4sin² θ = 3(1+ cos θ), 0° <
θ < 90°, then what is the value of (2tan θ + 4sinθ - secθ)?Solution
4 (1 - cos2 θ) = 3 + 3cos θ ⇒ 4 - 4cos2 θ = 3 + 3cos θ ⇒ 4cos2 θ + 3cos θ - 1 = 0 ⇒ 4cos2 θ + 4cos θ - cos θ - 1 = 0 ⇒ 4cos θ (cos θ + 1) - 1 (cos θ + 1) = 0 ⇒ (4cos θ - 1) (cos θ + 1) = 0 ⇒ cos θ + 1 = 0 ⇒ cos θ = - 1 [Not possible because 0° < θ < 90] ⇒ 4cos θ - 1 = 0 ⇒ cos θ = 1/4 We can get all value by using the image below, 
The height will be = √(42 - 12) = √(16 - 1) = √15 So, (2tan θ + 4sin θ - sec θ) = (2 × √15) + (4 × √15/4) - 4 = 2√15 + √15 - 4 = 3√15 - 4
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Select the combination of letter when placed sequentially in the blanks of the given series will complete the series.
L E __ P L E __ __ __ E A P L E __ P
Select the set in which the numbers are related in the same way as are the numbers of the following set.
(12, 27, 21)
Complete the analogy.
81 : 45 :: 72 : ?
Select the option that is related to the fifth number in the same way as the second number is related to first number and third number is related to f...
Select the option that is related to third letter- cluster in the same way as the second – letter cluster is related to the first letter- cluster.
...Select the option that is related to the third number in the same way as the second number is related to first number and the sixth number is related t...
Select the option that is related to third number-cluster in the same way first number cluster is related to second number-cluster.
83: 73 ...Select the combination of letters that when sequentially placed in the blanks of the given letter series will complete the series.
R _ _ T U V...
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