Question 17If $\theta$ is an acute angle and $\sin2\theta=a,$ then $\sin\theta+\cos\theta$ equals$\sqrt{a+1}$$(\sqrt2-1)a+1$$\sqrt{a+1}-\sqrt{a^2-a}$$\sqrt{a+1}+\sqrt{a^2-a}$$\sqrt{a+1}+a^2-a$