Question

How to solve if sin x=0.76 what is cos x=

Answer 1

`\bf sin^2(\theta)+cos^2(\theta)=1\implies cos^2(\theta )=1-sin^2(\theta ) \\\\\\ cos(\theta )=\pm √(1-sin^2(\theta ))\\\\ -------------------------------\\\\ cos(x)=\pm √(1-sin^2(x))\implies cos(x)=\pm √(1-(0.76)^2) \\\\\\ cos(x)=\pm √(0.4224)\implies cos(x)\approx \pm 0.64992307`