Ch 3 Checkpoint Questions

The following program skeleton asks for an angle in degrees and converts it to radians. The formatting of the final output is left to you. #include <iostream> #include <iomanip> using namespace std; int main( ) { const double PI = 3.14159; double degrees, radians; cout << "Enter an angle in degrees and I will convert it \n"; cout << "to radians for you: "; cin >> degrees; radians = degrees * PI / 180; // Displaying the value in radians left justified, in fixed //point notation, with 4 places of precision, in a field //5 spaces wide, making sure the decimal point is always //displayed. return 0; }

#include <iostream> #include <iomanip> using namespace std; int main() { const double PI = 3.14159; double degrees, radians; cout << "Enter an angle in degrees and I will convert it\n"; cout << "to radians for you: "; cin >> degrees; radians = degrees * PI / 180; cout << degrees << " degrees is equal to "; cout << setw(5) << left << fixed << showpoint << setprecision(4) << radians << " radians.\n"; return 0; }

The following program will not compile because the lines have been mixed up. #include <iomanip> } cout << person << endl; string person = "Wolfgang Smith"; int main() cout << person << endl; { #include <iostream> return 0; cout << left; using namespace std; cout << setw(20); cout << right; When the lines are properly arranged the program should display the following: Wolfgang Smith Wolfgang Smith Rearrange the lines in the correct order. Test the program by entering it on the computer, compiling it, and running it.

#include <iostream> #include <string> using namespace std; int main() { string person = "Wolfgang Smith"; cout << right; cout << setw(20); cout << person << endl; cout << left; cout << person << endl; return 0; }

What will he following program display? #include <iostream> using namespace std; int main() { int unus, duo, tres; unus = duo = tres; unus += 4; duo *= 2; tres -= 2; unus /= 3; duo += tres; cout << unus << endl; cout << duo << endl; cout << tres << endl; return 0; }

3 11 1

Assume the following variable definitions: int a = 5, b = 12; double x = 3.4, z = 9.1; What are the values of the following expressions? A) b / a B) x * a C) static_cast<double>(b / a) D) static_cast<double>(b) / a E) b /static_ cast<double>(a) F)static_ cast<double>(b) / static_ cast<double>(a) G) b / static_ cast<int>(x) H) static_ cast<int>(x) * static_ cast<int>(z) I) static_ cast<int>(x * z) J) static_cast<double>(static_ cast<int>(x) * static_ cast<int> (z) )

A) 2 B) 17.0 C) 2.0 D) 2.4 E) 2.4 F) 2.4 G) 4 H) 27 I) 30 J) 27.0

Write cout statements with stream manipulators that perform the following: A) Display the number 34.789 in a field of nine spaces with two decimal places of precision. B) Display the number 7.0 in a field of five spaces with three decimal places of percision. The decimal point and any trailing zeroes should be displayed. C) Display the number 5.789e+12 in fixed point notation. D) Display the number 67 left justified in a field of seven spaces.

A) cout << setw(9) << fixed << setprecision(2) << 34.789; B) cout << setw(5) << fixed << setprecision(3) << 7.0; C) cout << fixed << 5.789e12; D) cout << left << setw(7) << 67;

Write statements using combined assignment operators to perform the following: A) Add 6 to x B) Subtract 4 from amount. C) Multiply y by 4. D) Divide total by 27. E) Store in x the remainder of x divided by 7. F) Add y *5 to x. G) Subtract discount times 4 from total. H) Multiply increase by salesRep times 5. I) Divide profit by shares minus 1000.

A) x += 6; B) amount −= 4; C) y *= 4; D) total /= 27; E) x %= 7; F) x += (y * 5); G) total −= (discount * 4); H) increase *= (salesRep * 5); I) profit /= (shares − 1000);

Assume value is an integer variable. If the user enters 3.14 in response to the following programming statement, what will be stored in value? cin >> value; A) 3.14 B) 3 C) 0 D) Nothing. An error message is displayed.

B. 3

A program has the following variable definitions. long miles; int feet; float inches; Write one cin statement that reads a value into each of these variables.

cin >> miles >> feet >> inches;

Write a short description of each of the following functions: cos log sin exp log10 sqrt fmod pow tan

cos: Returns the cosine of the argument. exp: Returns the exponential function of the argument. fmod: Returns the remainder of the first argument divided by the second argument. log: Returns the natural logarithm of the argument. log10: Returns the base-10 logarithm of the argument. pow: Returns the value of the first argument raised to the power of the second argument. sin: Returns the sine of the argument. sqrt: Returns the square root of the argument. tan: Returns the tangent of the argument.

What header file must be included in programs using cin?

iostream

Write a multiple assignment that assigns 0 to the variables total, subtotal, tax, and shipping.

total = subtotal = tax = shipping = 0;

Assume the variables angle1 and angle2 hold angles stored in radians.Write a statement that adds the sine and angle1 to the cosine of angle2 and stores the result in the variable x.

x = sin(angle1) + cos(angle2);

The cosecant of the angle a is (1/sin a) Write a statement that calculates the cosecant of the angle stored in the variable a, and stores it in the variable y.

y = 1 / sin(a);

Write C++ expressions for the following algebraic expressions: y = 6x a = 2b + 4c y = x^2 g = x +2 / z^2 y = x^2 / z^2

y = 6 * x; a = 2 * b + 4 * c; y = x * x; or y = pow(x, 2.0); g = (x + 2) / (z * z); or g = (x + 2.0) / pow(z, 2.0); y = (x * x) / (z * z); or y = pow(x, 2.0) / pow (z, 2.0);

To find the cube root (the third root) of a number, raise it to the power of (1/3). To find the fourth root of a number, raise it to the power (1/4). Write a statement that will find the fifth root of the variable x and store the result in the variable y.

y = pow(x, 0.2); // 0.2 is equal to 1/5