A) 2
B) 1
C) -1
D) 0
Correct Answer: D
Solution :
\[\because \] \[\cos x+{{\cos }^{2}}x=1\] \[\Rightarrow \] \[\cos x=1-{{\cos }^{2}}x\] \[={{\sin }^{2}}x\] \[{{\sin }^{12}}x+3{{\sin }^{10}}x+3{{\sin }^{8}}x+{{\sin }^{6}}x-1\] \[={{\cos }^{6}}x+3{{\cos }^{5}}x+3{{\cos }^{4}}x+{{\cos }^{3}}x-1\] \[={{({{\cos }^{2}}x+\cos x)}^{3}}-1=1-1=0\]You need to login to perform this action.
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