How many integers $a$ are there such that the curve $y = a x ^ { 2 } - 2 \sin 2 x$ has an inflection point? [3 points] (1) 4 (2) 5 (3) 6 (4) 7 (5) 8
How many integers $a$ are there such that the curve $y = a x ^ { 2 } - 2 \sin 2 x$ has an inflection point? [3 points]\\
(1) 4\\
(2) 5\\
(3) 6\\
(4) 7\\
(5) 8