Q. find ∫01(f(x)−g(x))dx, if ∫01(f(x)−2g(x))dx=6, ∫01(2f(x)+2g(x))dx=9
Equations Addition: We have two equations:1. ∫01(f(x)−2g(x))dx=62. ∫01(2f(x)+2g(x))dx=9Let's add these two equations to eliminate g(x).
Integrals Addition: Adding the integrals:∫01((f(x)−2g(x))dx)+∫01((2f(x)+2g(x))dx)=6+9∫01(f(x)−2g(x)+2f(x)+2g(x))dx=15
Integrand Simplification: Simplify the integrand: \int_{\(0\)}^{\(1\)}(f(x)\(-2g(x) + 2f(x)+2g(x))\,dx = \int_{0}^{1}(3f(x))\,dx
Integral Calculation: Now we calculate the integral of 3f(x) from 0 to 1: ∫01(3f(x))dx=15
Integral Division: To find ∫01(f(x)dx), we divide both sides by 3:3∫01(3f(x))dx=315∫01(f(x))dx=5
Integral Substitution: Now we need to find ∫01(g(x)dx). We can use the first given integral for that:∫01((f(x)−2g(x))dx)=6We already know ∫01(f(x)dx)=5, so we substitute that in:5−∫01(2g(x))dx=6
Integral Solving: Solve for ∫01(2g(x))dx:∫01(2g(x))dx=5−6∫01(2g(x))dx=−1
Integral Division: Divide by 2 to find ∫01(g(x))dx: 2∫01(2g(x))dx=−21∫01(g(x))dx=−21
Final Value Calculation: Finally, we find ∫01(f(x)−g(x))dx using the values we found:∫01f(x)dx−∫01g(x)dx=5−(−21)
Final Value Calculation: Finally, we find ∫01(f(x)−g(x))dx using the values we found:∫01(f(x))dx−∫01(g(x))dx=5−(−21)Calculate the final value:5−(−21)=5+215+21=5.5
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