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If `A ={ theta : 2cos^2 theta + sintheta |
Answer» `because 2cos^(2)theta+sinthetale2` `therefore 2(1-sin^(2)theta)+sinthetale2` `implies 2sin^(2)theta-sinthetage0` `implies sintheta(2sintheta-1)ge0` `implies sintheta(sintheta-(1)/(2))ge0` `therefore sinthetale0andsinthetage(1)/(2)` Now, the values of `theta` which lie in teh interval `(pi)/(2)lethetale(3pi)/(2)[because B={theta:(pi)/(2)lethetale(3pi)/(2)}]` So, `theta` satisfy `sin theta le 0` in the interval `(pi)/(2)lethetale(5pi)/(6)`. `therefore AnnB={theta:pilethetale(3pi)/(2)}` and `AnnB={theta:(pi)/(2)lethetale(5pi)/(6)}` Hence, `AnnB={theta:(pi)/(2)lethetale(5pi)/(6)orpilethetale(3pi)/(2)}` `={theta:thetain[(pi)/(2)(5pi)/(6)]uu[pi,(3pi)/(2)]}` |
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