Question Number 68353 by mhmd last updated on 09/Sep/19 | ||
$$\mathrm{If}\:\mathrm{sin}\:{x}+\mathrm{sin}^{\mathrm{2}} {x}=\mathrm{1},\:\mathrm{then}\:\mathrm{value}\:\mathrm{of} \\ $$$$\mathrm{cos}^{\mathrm{2}} {x}+\mathrm{cos}^{\mathrm{4}} {x}\:\:\mathrm{is} \\ $$ | ||
Answered by $@ty@m123 last updated on 09/Sep/19 | ||
$${Given}\:,\:\mathrm{1}−\mathrm{sin}\:^{\mathrm{2}} {x}=\mathrm{sin}\:{x} \\ $$$$\mathrm{cos}\:^{\mathrm{2}} {x}=\mathrm{sin}\:{x}\:\:\:....\left(\mathrm{1}\right) \\ $$$$\therefore\:\mathrm{cos}^{\mathrm{2}} {x}+\mathrm{cos}^{\mathrm{4}} {x}\:\: \\ $$$$=\mathrm{sin}\:{x}+\mathrm{sin}^{\mathrm{2}} {x}=\mathrm{1} \\ $$ | ||