The correct option is B x>−7
Given, 1−x2<4
Step 1: Multiply both sides of the equation by 2 to eliminate 2 on the left side of the equation.
Also, multiplying both sides of the inequality by a positive number does not change the direction of the inequality.
1−x2×2<4×2
⇒1−x<8
Step 2: Subtract both sides of the equation by 1 to eliminate 1 on the left side of the equation.
Also, subtracting both sides of the inequality by a positive number does not change the direction of the inequality.
1−x−1<8−1
−x<7
Step 3: Divide both sides of the equation by -1.
Also, dividing both sides of the inequality by a negative number changes the direction of the inequality.
−x−1>7−1
x>−7
Hence, solution of the inequality 1−x2<4 is x>−7.