Toggle navigation
Home
Article Category
Question Papers
General Knowlege
Popular Pages
Multiple Choice Question in 049
Multiple Choice Question in
Multiple Choice Question in TRADES-INSTRUCTOR---GR-II---SMITHY---TECHNICAL-EDUCATION
Multiple Choice Question in -current-affairs-2016
Question Answer in ASSISTANT-PROFESSOR---COMPUTER-SCIENCE-AND-ENGINEERING---TECHNICAL-EDUCATION
Multiple Choice Question in ASSISTANT-PROFESSOR---COMPUTER-SCIENCE-AND-ENGINEERING---TECHNICAL-EDUCATION
Multiple Choice Question in english
Multiple Choice Question in abbreviations-abbreviations-m
Multiple Choice Question in SSC CHSL 7 March 2018 Morning Shift
Multiple Choice Question in 072/2016
Multiple Choice Question in 100/2016
Question Answer Bank
Multiple Choice Question Bank
Question Answer Category
Multiple Choice Question Category
Home
->
Multiple Choice Questions
1. If $$sin θ + sin^2θ + sin^3θ = 1$$, then $$cos^6θ - 4cos^4θ + 8cos^2θ$$ is equal to
(A): 2
(B): 1
(C): 4
(D): 3
Previous Question
Show Answer
Next Question
Add Tags
Report Error
Show Marks
Write Comment
Type in
(Press Ctrl+g to toggle between English and the chosen language)
Post reply
Comments
By: anil on 05 May 2019 01.50 am
Expression : $$sin θ + sin^2θ + sin^3θ = 1$$ => $$sin heta + sin^3 heta = 1 - sin^2 heta$$ => $$sin heta (1 + sin^2 heta) = cos^2 heta$$ Squaring both sides => $$(sin^2 heta) (1 + sin^2 heta)^2 = cos^4 heta$$ => $$(1 - cos^2 heta) (1 + 1 - cos^2 heta)^2 = cos^4 heta$$ => $$(1 - cos^2 heta) (4 - 4cos^2 heta + cos^4 heta) = cos^4 heta$$ => $$4 - 4cos^2 heta + cos^4 heta - 4cos^2 heta + 4cos^4 heta - cos^6 heta = cos^4 heta$$ => $$- cos^6 heta + 4cos^4 heta - 8cos^2 heta + 4 = 0$$ => $$cos^6 heta - 4cos^4 heta + 8cos^2 heta = 4$$
Tags
SSC CGL 2012 Tier 1 8 July NZ Evening II
Show Similar Question And Answers
QA->Which two leading cos in taper roller bearings are merging in India ?....
QA->ALL ARE EQUAL, BUT SOME ARE MORE EQUAL THAN OTHERS WHO SAID THIS....
QA->If i=√-1 then the sum of i+i2+i3+…. 100 terms is equal to:....
QA->If the progression 3, 20, 17,… and 63, 65, 67….. are such that their nth terms are equal, then the value of n is:....
QA->A cyclist goes 40 km towards East and then turning to right he goes 40 km. Again he turn to his left and goes 20 km. After this he turns to his left and goes 40 km, then again turns right and goes 10km. How far is he from his starting point?....
MCQ->If $$sin θ + sin^2θ + sin^3θ = 1$$, then $$cos^6θ - 4cos^4θ + 8cos^2θ$$ is equal to....
MCQ->The value of $$(\frac{\cos^2A(\sin A+\cos A)}{cosec^2A(\sin A- \cos A)}+\frac{sin^2(sin A - cos A}{sec^2 A(sin A(sinA+cos A})$$....
MCQ->The value of the expression $$Sin^{2}1^\circ+Sin^{2}11^\circ+Sin^{2}21^\circ+Sin^{2}31^\circ+Sin^{2}41^\circ+Sin^{2}45^\circ$$$$+Sin^{2}49^\circ+Sin^{2}59^\circ+Sin^{2}69^\circ+Sin^{2}79^\circ+Sin^{2}89^\circ$$....
MCQ->If $$x sin^3 θ + y cos^3 θ = sin θ cos θ$$ and x sin θ = y cos θ, sin θ ≠ 0, cos θ ≠ 0, then $$x^2 + y^2$$ is....
MCQ->Value of the expression: $$\frac{1+2\ Sin\ 60^\circ Cos\ 60^\circ}{Sin\ 60^\circ + Cos\ 60^\circ}+\frac{1-2\ Sin\ 60^\circ Cos\ 60^\circ}{Sin\ 60^\circ - Cos\ 60^\circ}$$ ....
×
×
Type The Issue
×
Your Marks
Terms And Service:We do not guarantee the accuracy of available data ..We Provide Information On Public Data.. Please consult an expert before using this data for commercial or personal use
Powered By:Omega Web Solutions
© 2002-2017 Omega Education PVT LTD...
Privacy
|
Terms And Conditions