编写计算表达式x^2-5x+4值的函数funt，用x作为参数调用此函数，分别计算下面各式的值：y1=x^2-5*×+4，y2=(x+15)^2-5×(x+15)+4，y3=(sinx)^2-5×sinx+4。 **输入格式要求："%lf" 提示信息："Input x: " **输出格式要求："x =\t%5.2f\n" "y1=\t%5.2f\n" "y2=\t%5.2f\n" "y3=\t%5.2f\n" 程序运行示例如下： Input x: 3.5 x = 3.50 y1= -1.25 y2= 253.75 y3= 5.88

以下是函数funt的代码实现：

#include <stdio.h>
#include <math.h>

double funt(double x) {
    double y1 = pow(x, 2) - 5 * x + 4;
    double y2 = pow(x + 15, 2) - 5 * (x + 15) + 4;
    double y3 = pow(sin(x), 2) - 5 * sin(x) + 4;
    return y1 + y2 + y3;
}

int main() {
    double x;
    printf("Input x: ");
    scanf("%lf", &x);
    double result = funt(x);
    printf("x =\t%5.2f\n", x);
    printf("y1=\t%5.2f\n", pow(x, 2) - 5 * x + 4);
    printf("y2=\t%5.2f\n", pow(x + 15, 2) - 5 * (x + 15) + 4);
    printf("y3=\t%5.2f\n", pow(sin(x), 2) - 5 * sin(x) + 4);
    printf("funt(x) =\t%5.2f\n", result);
    return 0;
}

程序运行示例如下：

Input x: 3.5
x =     3.50
y1=    -1.25
y2=   253.75
y3=     5.88
funt(x) =   258.38