====== Question 6 & 7, Review Exercise ====== Solutions of Question 6 & 7 of Review Exercise of Unit 05: Polynomials. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. =====Question 6===== Find the value of ' $k$ ' so that the remainder upon dividing $\left(x^{2}+8 x+k\right)$ by $(x-4)$ is zero. ** Solution. ** Let \( p(x) = x^{2} + 8x + k \). We are given that the remainder upon dividing \( p(x) \) by \( (x - 4) \) is zero. \\ By the remainder theorem, the remainder is \( p(4) \). Since \( p(4) = 0 \), we have: \begin{align*} p(4) &= (4)^2 + 8(4) + k \\ &= 16 + 32 + k \\ &= 48 + k. \end{align*} For the remainder to be zero: \[ 48 + k = 0. \] Thus, \[ k = -48. \] =====Question 7===== Suppose that the quotient upon dividing one polynomial by another is $3 x^{2}-x+32-\frac{121}{x+4}$. What is the dividend? ** Solution. ** :!: The question doesn't seem to solvable. ====Go to ==== [[math-11-nbf:sol:unit05:Re-ex-p3|< Question 3 &4]] [[math-11-nbf:sol:unit05:Re-ex-p5|Question 8>]]