Question

PLS HELP, HAVE A GOOD DAY

Answer 1

• 2sin²x-1=0
• 2sin²x=1
• sin²x=1/2
• sinx=1/√2

So

x:-

• nπ/2+π/4

Answer 2

`(\pi )/(4) +(\pi )/(2) n,` where n∈Z.

Explanation:

2sin²x-1; ⇒ sin²x=1/2;

`\left[\begin{array}{ccc}sinx=-(1)/(√(2)) \\sinx=(1)/(√(2)) \end{array} \ = > \ \left[\begin{array}{ccc}x=(-1)^(l+1)(\pi )/(4)+\pi l \\x=(-1)^k(\pi )/(4)+\pi k \end{array} \ = > x=(\pi )/(4) +(\pi )/(2)n, \ n-Z.`