Question

cos(п+x)=корень2/2

cos(x-3п)=1

Answer 1

$1) cos(pi+x) = frac{sqrt{2}}{2}\ pi+x = +-arccosfrac{sqrt{2}}{2} + 2pi n , neZ\ pi+x = +-frac{{pi}}{4} + 2pi n , neZ\ x1 = frac{{pi}}{4} -pi + 2pi n , neZ\ x1 = - frac{{3pi}}{4} + 2pi n , neZ\ \ x2 = - frac{{pi}}{4} -pi + 2pi n , neZ\ x2 = - frac{{5pi}}{4} + 2pi n , neZ$

 

$2)<var>cos(x-frac{3}{pi})=1\ x-frac{3}{pi} = 2pi n , neZ\ x=frac{3}{pi} +2pi n , neZ\</var>$