If tan θ = (17)\Big(\dfrac{1}{\sqrt{7}}\Big)(71), then the value of (cosec2θ+sec2θcosec2θ−sec2θ)\Big(\dfrac{\cosec^2\theta + \sec^2\theta}{\cosec^2\theta - \sec^2\theta}\Big)(cosec2θ−sec2θcosec2θ+sec2θ) is:
(34)\Big(\dfrac{3}{4}\Big)(43)
(43)\Big(\dfrac{4}{3}\Big)(34)
(37)\Big(\dfrac{3}{7}\Big)(73)
(47)\Big(\dfrac{4}{7}\Big)(74)
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Given,
tan θ = (17)\Big(\dfrac{1}{\sqrt{7}}\Big)(71)
tan2 θ = (17)\Big(\dfrac{1}{7}\Big)(71)
We know that,
sec2θ=1+tan2θsec2θ=1+17sec2θ=87.cosec2θ=1+cot2θcosec2θ=1+7cosec2θ=8.\sec^2 \theta = 1 + \tan^2 \theta \\[1em] \sec^2 \theta = 1 + \dfrac{1}{7} \\[1em] \sec^2 \theta = \dfrac{8}{7}. \\[1em] \cosec^2 \theta = 1 + \cot^2 \theta \\[1em] \cosec^2 \theta = 1 + 7 \\[1em] \cosec^2 \theta = 8.sec2θ=1+tan2θsec2θ=1+71sec2θ=78.cosec2θ=1+cot2θcosec2θ=1+7cosec2θ=8.
Given expression,
⇒(cosec2θ+sec2θcosec2θ−sec2θ)⇒8+878−87⇒56+8756−87⇒6448=43.\Rightarrow \Big(\dfrac{\cosec^2\theta + \sec^2\theta}{\cosec^2\theta - \sec^2\theta}\Big) \\[1em] \Rightarrow \dfrac{8 + \dfrac{8}{7}}{8 - \dfrac{8}{7}} \\[1em] \Rightarrow \dfrac{\dfrac{56 + 8}{7}}{\dfrac{56 - 8}{7}} \\[1em] \Rightarrow \dfrac{64}{48} = \dfrac{4}{3}.⇒(cosec2θ−sec2θcosec2θ+sec2θ)⇒8−788+78⇒756−8756+8⇒4864=34.
Hence, option 2 is the correct option.
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If cot A + (1cotA)\Big(\dfrac{1}{\cot A}\Big)(cotA1) = 2, then cot2A + (1cot2A)\Big(\dfrac{1}{\cot^2 A}\Big)(cot2A1) equals:
0
1
2
4
If 4 tan θ = 3, then (4sinθ−3cosθ4sinθ+3cosθ)\Big(\dfrac{4\sin\theta - 3\cos\theta}{4\sin\theta + 3\cos\theta}\Big)(4sinθ+3cosθ4sinθ−3cosθ) = ?
(13)\Big(\dfrac{1}{3}\Big)(31)
(23)\Big(\dfrac{2}{3}\Big)(32)
(1 + sin A)(1 − sin A) is equal to:
cosec2A
sin2A
sec2A
cos2A
sin A expressed in terms of cot A is:
(11+cot2A)\Big(\dfrac{1}{\sqrt{1 + \cot^2 A}}\Big)(1+cot2A1)
(1+cot2AcotA)\Big(\dfrac{\sqrt{1 + \cot^2 A}}{\cot A}\Big)(cotA1+cot2A)
(1+cot2A1)\Big(\dfrac{\sqrt{1 + \cot^2 A}}{1}\Big)(11+cot2A)
(1−cot2AcotA)\Big(\dfrac{\sqrt{1 - \cot^2 A}}{\cot A}\Big)(cotA1−cot2A)