JEE Main 2021 · 17 March · Evening Shift · Mathematics · Area Under Curves
Let f: [ - 3, 1 ] → R be given as f(x) = \ cases min\ ( x + 6 ) , x...
Let f:[−3,1]→R be given as f\left(x\right) = \left\{\begin{cases}min\left\{( x + 6 ) , {x}^{2}\right\}, & - 3 \le x \le 0 \\ max\left\{\sqrt{x}, {x}^{2}\right\}, & 0 \le x \le 1\end{cases}.\right)If the area bounded byy = f ( x )andx-axis is A sq units, then the value of 6A is equal to
Correct answer
0
Step-by-step solution
Given f:[−3,1]→R,f\left(x\right) = \left\{\begin{cases}min\left\{( x + 6 ) , {x}^{2}\right\}, & - 3 \le x \le 0 \\ max\left\{\sqrt{x}, {x}^{2}\right\}, & 0 \le x \le 1\end{cases}\right)</p><p>We havex + 6 = {x}^{2}</p><p>⇒ {x}^{2} - x - 6 = 0</p><p>⇒ \left(x - 3\right)\left(x + 2\right) = 0</p><p>⇒ x = 3 \text{ and } - 2 .</p><p>Also,\sqrt{x} = {x}^{2}</p><p>⇒ {x}^{2} - \sqrt{x} = 0</p><p>⇒ \sqrt{x}\left(x\dfrac{3}{2} - 1\right) = 0</p><p>⇒ x = 0 \text{ and } x = 1 .</p><p>Hence,theregionboundedbyf\left(x\right)isgivenbythefollowinggraph.</p><p><imgsrc="https://cdn−question−pool.getmarks.app/pyq/jeemain/ff16e49b−d258−450e−a72a−6da11e5d0936−image.png"style="width:397px;height:350px;"/></p><p>Hence,theareaboundedbyy = f ( x )andx-axis is