Q. P(x) is a polynomial. Here are a few values of P(x): P(−6)=3P(−4)=−1P(4)=2P(6)=−5
Write Given Values: Write down the given values. P(−6)=3, P(−4)=−1, P(4)=2, P(6)=−5
Assume Polynomial Degree: Assume P(x) is a polynomial of degree 3 (cubic polynomial). P(x)=ax3+bx2+cx+d
Substitute x Values: Substitute x=−6 into the polynomial equation. \[ 3 = a(-6)^3 + b(-6)^2 + c(-6) + d \] \[ 3 = -216a + 36b - 6c + d \]
Write System of Equations: Substitute x=−4 into the polynomial equation. −1=a(−4)3+b(−4)2+c(−4)+d−1=−64a+16b−4c+d
Solve System of Equations: Substitute x=4 into the polynomial equation. 2=a(4)3+b(4)2+c(4)+d2=64a+16b+4c+d
Simplify Equation: Substitute x=6 into the polynomial equation. −5=a(6)3+b(6)2+c(6)+d−5=216a+36b+6c+d
Solve for b and d: Write the system of equations. \[-216a + 36b - 6c + d = 3\] \[-64a + 16b - 4c + d = -1\] \[64a + 16b + 4c + d = 2\] \[216a + 36b + 6c + d = -5\]
Substitute b to Find d: Solve the system of equations. Add equations 1 and 4: −216a+36b−6c+d+216a+36b+6c+d=3−572b+2d=−2
Substitute b and d: Simplify the equation. 36b+d=−1
Solve for a and c: Add equations 2 and 3: −64a+16b−4c+d+64a+16b+4c+d=−1+232b+2d=1
Solve System for a and c: Simplify the equation. 16b+d=0.5
Substitute a to Find c: Solve for b and d. From 36b+d=−1 and 16b+d=0.5: 36b+d−(16b+d)=−1−0.520b=−1.5b=−0.075
Substitute a to Find c: Solve for b and d. From 36b+d=−1 and 16b+d=0.5: 36b+d−(16b+d)=−1−0.520b=−1.5b=−0.075 Substitute b back to find d. 16(−0.075)+d=0.5−1.2+d=0.5d=1.7
Substitute a to Find c: Solve for b and d. From 36b+d=−1 and 16b+d=0.5: 36b+d−(16b+d)=−1−0.520b=−1.5b=−0.075 Substitute b back to find d. 16(−0.075)+d=0.5−1.2+d=0.5d=1.7 Substitute b and d into original equations to find a and c. −216a+36(−0.075)−6c+1.7=3−216a−2.7−6c+1.7=3−216a−6c=4
Substitute a to Find c: Solve for b and d. From 36b+d=−1 and 16b+d=0.5: 36b+d−(16b+d)=−1−0.520b=−1.5b=−0.075 Substitute b back to find d. 16(−0.075)+d=0.5−1.2+d=0.5d=1.7 Substitute b and d into original equations to find a and c. −216a+36(−0.075)−6c+1.7=3−216a−2.7−6c+1.7=3−216a−6c=4 Solve for a and c. −64a+16(−0.075)−4c+1.7=−1−64a−1.2−4c+1.7=−1−64a−4c=−1.5
Substitute a to Find c: Solve for b and d. From 36b+d=−1 and 16b+d=0.5: 36b+d−(16b+d)=−1−0.520b=−1.5b=−0.075 Substitute b back to find d. 16(−0.075)+d=0.5−1.2+d=0.5d=1.7 Substitute b and d into original equations to find a and c. −216a+36(−0.075)−6c+1.7=3−216a−2.7−6c+1.7=3−216a−6c=4 Solve for a and c. −64a+16(−0.075)−4c+1.7=−1−64a−1.2−4c+1.7=−1−64a−4c=−1.5 Solve the system of equations for a and c. −216a−6c=4−64a−4c=−1.5
Substitute a to Find c: Solve for b and d. From 36b+d=−1 and 16b+d=0.5: 36b+d−(16b+d)=−1−0.520b=−1.5b=−0.075 Substitute b back to find d. 16(−0.075)+d=0.5−1.2+d=0.5d=1.7 Substitute b and d into original equations to find a and c. −216a+36(−0.075)−6c+1.7=3−216a−2.7−6c+1.7=3−216a−6c=4 Solve for a and c. −64a+16(−0.075)−4c+1.7=−1−64a−1.2−4c+1.7=−1−64a−4c=−1.5 Solve the system of equations for a and c. −216a−6c=4−64a−4c=−1.5 Simplify and solve. Multiply second equation by 1.5: −96a−6c=−2.25−216a−6c−(−96a−6c)=4−(−2.25)−120a=6.25a=−0.052
Substitute a to Find c: Solve for b and d. From 36b+d=−1 and 16b+d=0.5: 36b+d−(16b+d)=−1−0.520b=−1.5b=−0.075 Substitute b back to find d. 16(−0.075)+d=0.5−1.2+d=0.5d=1.7 Substitute b and d into original equations to find a and c. −216a+36(−0.075)−6c+1.7=3−216a−2.7−6c+1.7=3−216a−6c=4 Solve for a and c. −64a+16(−0.075)−4c+1.7=−1−64a−1.2−4c+1.7=−1−64a−4c=−1.5 Solve the system of equations for a and c. −216a−6c=4−64a−4c=−1.5 Simplify and solve. Multiply second equation by 1.5: −96a−6c=−2.25−216a−6c−(−96a−6c)=4−(−2.25)−120a=6.25a=−0.052 Substitute a back to find c. −64(−0.052)−4c=−1.53.328−4c=−1.5−4c=−4.828c=1.207
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