Question 1202274
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<pre>

Replace  sin^2(x)  by  (1-cos^2(x)).  You will get


    4cos^2(x) - 3sin^2(x) = 4cos^2(x) - 3(1-cos^2(x)) = 7cos^2(x) - 3.    <U>ANSWER</U>
</pre>

Solved, completed and explained.


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To avoid a non-mathematical accent, use a proper &nbsp;Math language: 


&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;" express &nbsp;4cos^2(x) - 3sin^2(x) &nbsp;in terms of &nbsp;cos(x) ".