document.write( "Question 1209561: If 7^sin²x - 7^cos²x = 8
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document.write( "find the value of x.
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Algebra.Com's Answer #849523 by ikleyn(53763) You can put this solution on YOUR website! . \n" ); document.write( "If 7^sin²x - 7^cos²x = 8 \n" ); document.write( "find the value of x. \n" ); document.write( "~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "The starting equation is\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " 7^(sin^2(x)) - 7^(cos^2(x)) = 8.\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Due to OBVIOUS reasons, this equation has no real solutions.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Indeed, sin^2(x) has the maximum value of 1; hence, 7^(sin^2(x)) has maximum value of 7.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Next, from 7^(sin^2(x)), the equation subtracts 7^(cos^2(x)), which is non-negative \n" ); document.write( "real number, so the left side of the equation CAN NOT be greater than 7.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " A fortiori, it can not be 8.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "At this point, my solution is complete, and the \r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "ANSWER is: this given equation has no solution/solutions in real numbers.\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |